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Just Accepted manuscripts are peer-reviewed and accepted for publication. They are posted online prior to technical editing formatting for publication and author proofing.
Display Method:
, Available online ,
doi: 10.11884/HPLPB202537.240285
Abstract:
In order to carry out research on the overall technology of C-band miniaturized accelerators under the conditions of localization, the Institute of Applied Electronics of the Chinese Academy of Engineering Physics has developed various C-band miniaturized standing wave accelerator tubes. At the same time, a C-band accelerator X-ray source system with domestic components (magnetron, ring resonator, high-voltage power supply, etc.) as the main components has been established, and further high-power hot test experiments have been carried out using the accelerator as a testing platform. In the hot test experiment, the main performance indicators of the accelerator were tested according to the testing principles and methods specified in the national standard “GB/T 20129-2015 Electron Linear Accelerator for Non destructive Testing”. The energy of the accelerator was tested using the steel attenuation method, and the focal size of the accelerator was tested using the “sandwich” method. The final test results indicate that the accelerator focal size is approximately 1.2 mm, and the accelerator’s energy can be continuously adjusted within the range of 3 MeV～4 MeV. The dose rate fluctuation of the accelerator within 20 minutes is less than ± 3%. The research results indicate that the supporting environment and overall performance of domestic C-band miniaturized accelerator can basically meet the development and use requirements of miniaturized accelerator systems.
In order to carry out research on the overall technology of C-band miniaturized accelerators under the conditions of localization, the Institute of Applied Electronics of the Chinese Academy of Engineering Physics has developed various C-band miniaturized standing wave accelerator tubes. At the same time, a C-band accelerator X-ray source system with domestic components (magnetron, ring resonator, high-voltage power supply, etc.) as the main components has been established, and further high-power hot test experiments have been carried out using the accelerator as a testing platform. In the hot test experiment, the main performance indicators of the accelerator were tested according to the testing principles and methods specified in the national standard “GB/T 20129-2015 Electron Linear Accelerator for Non destructive Testing”. The energy of the accelerator was tested using the steel attenuation method, and the focal size of the accelerator was tested using the “sandwich” method. The final test results indicate that the accelerator focal size is approximately 1.2 mm, and the accelerator’s energy can be continuously adjusted within the range of 3 MeV～4 MeV. The dose rate fluctuation of the accelerator within 20 minutes is less than ± 3%. The research results indicate that the supporting environment and overall performance of domestic C-band miniaturized accelerator can basically meet the development and use requirements of miniaturized accelerator systems.
, Available online ,
doi: 10.11884/HPLPB202537.240083
Abstract:
Industrial linear accelerators are gradually moving towards high average beam power in a small, compact shapes. The beam break-up effect due to the transverse wakefield is the main limitation to its performance improvement. The hybrid dielectric-iris-loaded structure is a new a miniaturization accelerating structure with high average beam power. The main problem is difficulty in assembly and tuning.Through the study of dielectric based accelerating structures, a miniaturization accelerator with high average beam power was designed and optimized. During the research process, the influence of dielectric structural parameters on the accelerating structures size, accelerating gradient, and beam power was analyzed. The optimized accelerating structure size was reduced by about one-third compared to conventional iris-loaded accelerating structure .It can achieve the same acceleration gradient. The insertion of a simple dielectric tube into the dielectric structure made assembly and tuning easier. Through the study of dielectric based accelerating structures, a miniaturization accelerator with high average beam power was designed and optimized. This accelerator is operating at S-band that the frequency is2856 MHz and voltage amplitude is 2.5 MeV. During the research process, we complete the physical design of accelerator. Beam dynamics are calculated through numerical calculation methods and PARMELA. Our research provides a research basis for the further development of irradiation linear accelerators.
Industrial linear accelerators are gradually moving towards high average beam power in a small, compact shapes. The beam break-up effect due to the transverse wakefield is the main limitation to its performance improvement. The hybrid dielectric-iris-loaded structure is a new a miniaturization accelerating structure with high average beam power. The main problem is difficulty in assembly and tuning.Through the study of dielectric based accelerating structures, a miniaturization accelerator with high average beam power was designed and optimized. During the research process, the influence of dielectric structural parameters on the accelerating structures size, accelerating gradient, and beam power was analyzed. The optimized accelerating structure size was reduced by about one-third compared to conventional iris-loaded accelerating structure .It can achieve the same acceleration gradient. The insertion of a simple dielectric tube into the dielectric structure made assembly and tuning easier. Through the study of dielectric based accelerating structures, a miniaturization accelerator with high average beam power was designed and optimized. This accelerator is operating at S-band that the frequency is
, Available online ,
doi: 10.11884/HPLPB202537.240327
Abstract:
In order to understand the effect of laser focal spot size on the extreme ultraviolet conversion efficiency and the physical mechanism that produces the effect, we develops a two-dimensional transient expansion model of laser ablation of planar target for the first time to produce coronal plasma to study the effect of laser focal spot on the extreme ultraviolet conversion efficiency by means of theoretical analysis. We find that under condition with light intensity of 7.45×1010 W/cm2, full width at half maxima of 5 ns, wavelength of1064 nm, as the laser focal spot radius increases from 60 μm to 300 μm, the corresponding extreme ultraviolet conversion efficiency increases from 1% to 5.5%, while the corresponding extreme ultraviolet conversion efficiency stays at 5.5% after the focal spot radius is larger than 300 μm. 1% to 5.5%, while the corresponding extreme ultraviolet conversion efficiency remains at 5.5% after the focal spot radius is larger than 300 μm. This is due to the fact that the plasma in the coronal region generated by laser ablation of planar targets expands from the initial one-dimensional expansion to the subsequent two-dimensional expansion, which determines the saturation size of the plasma region emitting extreme ultraviolet light and ultimately determines the conversion efficiency of the extreme ultraviolet light. Our theoretical analysis resolved trend of conversion efficiency with focal spot radius can explain the physical phenomena observed in the laser ablation of a tin target experiment.
In order to understand the effect of laser focal spot size on the extreme ultraviolet conversion efficiency and the physical mechanism that produces the effect, we develops a two-dimensional transient expansion model of laser ablation of planar target for the first time to produce coronal plasma to study the effect of laser focal spot on the extreme ultraviolet conversion efficiency by means of theoretical analysis. We find that under condition with light intensity of 7.45×1010 W/cm2, full width at half maxima of 5 ns, wavelength of
, Available online ,
doi: 10.11884/HPLPB202537.240286
Abstract:
The Rhodotron is a compact and highly efficient accelerator. This accelerator requires an electron gun with high repetition frequency, short pulses and low emittance, to ensure optimal acceleration performance. This paper shows the physical design, simulation, prototype development and beam testing of such an electron gun. The electron gun is designed as a grid-controlled electron gun based on a barium-tungsten thermionic cathode. The electron gun adopts a Pierce structure. It has a cathode voltage -40 kV, an operating repetition frequency of 10.75 MHz, a design emission current of 200 mA maximum, and a single minimum pulse length of 3 ns. In the actual test, the electron gun measured a peak emission current of 204 mA with the cathode heater operating at 0.95 A/6.7 V, loaded cathode DC voltage -40 kV, and gate control voltage 290 V/10 MHz. When the beam pulse length is 2.7 ns, the beam current amplitude is 39.2 mA, and the actual beam emittance is less than 2 mm mrad. This result meets the design and accelerator application requirements.
The Rhodotron is a compact and highly efficient accelerator. This accelerator requires an electron gun with high repetition frequency, short pulses and low emittance, to ensure optimal acceleration performance. This paper shows the physical design, simulation, prototype development and beam testing of such an electron gun. The electron gun is designed as a grid-controlled electron gun based on a barium-tungsten thermionic cathode. The electron gun adopts a Pierce structure. It has a cathode voltage -40 kV, an operating repetition frequency of 10.75 MHz, a design emission current of 200 mA maximum, and a single minimum pulse length of 3 ns. In the actual test, the electron gun measured a peak emission current of 204 mA with the cathode heater operating at 0.95 A/6.7 V, loaded cathode DC voltage -40 kV, and gate control voltage 290 V/10 MHz. When the beam pulse length is 2.7 ns, the beam current amplitude is 39.2 mA, and the actual beam emittance is less than 2 mm mrad. This result meets the design and accelerator application requirements.
, Available online ,
doi: 10.11884/HPLPB202537.240312
Abstract:
With the increasing demand for diagnostics of high-energy-density (HED) materials, X-ray interferometric imaging technology has gained significant attention and application in this field. This paper primarily reviews the latest domestic and international advancements in X-ray interferometric imaging techniques and systems, focusing on the principles and capabilities of X-ray grating imaging based on Talbot and Talbot-Lau interferometry. Talbot and Talbot-Lau interferometry utilize gratings with periodic structures to perform high-precision measurements of X-ray phase, absorption, and scattering properties, enabling non-destructive inspection and imaging of internal structures of samples. This work summarizes the application of these techniques in diagnostic experiments for HED materials, introduces the Talbot Interferometric Analysis (TIA) code, and demonstrates an initial simulation by integrating the TIA program with the Flash hydrodynamics code. The simulation successfully retrieved three types of information: absorption, phase, and dark-field from the Flash model. Finally, the paper concludes with a summary and outlook on the application of X-ray Talbot-Lau interferometric diagnostic technology in high-energy-density plasma experiments.
With the increasing demand for diagnostics of high-energy-density (HED) materials, X-ray interferometric imaging technology has gained significant attention and application in this field. This paper primarily reviews the latest domestic and international advancements in X-ray interferometric imaging techniques and systems, focusing on the principles and capabilities of X-ray grating imaging based on Talbot and Talbot-Lau interferometry. Talbot and Talbot-Lau interferometry utilize gratings with periodic structures to perform high-precision measurements of X-ray phase, absorption, and scattering properties, enabling non-destructive inspection and imaging of internal structures of samples. This work summarizes the application of these techniques in diagnostic experiments for HED materials, introduces the Talbot Interferometric Analysis (TIA) code, and demonstrates an initial simulation by integrating the TIA program with the Flash hydrodynamics code. The simulation successfully retrieved three types of information: absorption, phase, and dark-field from the Flash model. Finally, the paper concludes with a summary and outlook on the application of X-ray Talbot-Lau interferometric diagnostic technology in high-energy-density plasma experiments.
Articles in press have been peer-reviewed and accepted, which are not yet assigned to volumes /issues, but are citable by Digital Object Identifier (DOI).
Display Method:
, Available online ,
doi: 10.11884/HPLPB202537.240358
Abstract:
Constructing a photoconductive semiconductor switch (PCSS)-metal coil structure, we discovered a new phenomenon of electromagnetic oscillation in vanadium-compensation semi-insulating (VCSI) PCSS. Here the PCSS responds to laser pulse and high-voltage signal while the metal coil generates an oscillating voltage pulse envelope signal. The generation of this oscillating signal is not related to the input bias voltage of the PCSS, the pulse circuit components, or the electrode structure of the PCSS, rather it is related to the output characteristic of the PCSS. This physical phenomenon can be explained using the current surge model in photoconducting antenna. Preparing ohmic contact electrode on the silicon carbide material forms the PCSS, which generates a large number of photogenerated carriers when ultra-fast laser pulses irradiate the surface of the material and Simultaneously applies a bias voltage signal between the electrode. At this time inside the PCSS the electric field causes the transient current, radiating electromagnetic wave to the metal coil to generate oscillating signal.
Constructing a photoconductive semiconductor switch (PCSS)-metal coil structure, we discovered a new phenomenon of electromagnetic oscillation in vanadium-compensation semi-insulating (VCSI) PCSS. Here the PCSS responds to laser pulse and high-voltage signal while the metal coil generates an oscillating voltage pulse envelope signal. The generation of this oscillating signal is not related to the input bias voltage of the PCSS, the pulse circuit components, or the electrode structure of the PCSS, rather it is related to the output characteristic of the PCSS. This physical phenomenon can be explained using the current surge model in photoconducting antenna. Preparing ohmic contact electrode on the silicon carbide material forms the PCSS, which generates a large number of photogenerated carriers when ultra-fast laser pulses irradiate the surface of the material and Simultaneously applies a bias voltage signal between the electrode. At this time inside the PCSS the electric field causes the transient current, radiating electromagnetic wave to the metal coil to generate oscillating signal.
, Available online ,
doi: 10.11884/HPLPB202537.240335
Abstract:
This paper discusses early experiments on indirect laser-driven implosion of double-metal-shell targets conducted with a hundred-kilojoule-class laser facility. The design of the double-metal-shell target is derived from the volume ignition scheme, which decouples the radiation ablation and implosion compression processes, thereby improving the robustness of the implosion. However, due to the high difficulty in manufacturing the double-metal-shell target, the neutron yield in the initial experiments was much lower than expected from simulations. To address this issue, two key improvements are proposed: first, optimizing the joint design of the outer shell to reduce the impact of hydrodynamic instability, thus to improve the collision efficiency of the inner and outer shells and the implosion efficiency of the inner core; second, enhancing the coupling efficiency of the hohlraum-target to improve the effective transfer of laser energy. With these improvements, the compression performance and implosion efficiency of the target were significantly enhanced, resulting in a substantial increase in neutron yield, from\begin{document}$ 5.0\times {10}^{7} $\end{document} ![]()
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This paper discusses early experiments on indirect laser-driven implosion of double-metal-shell targets conducted with a hundred-kilojoule-class laser facility. The design of the double-metal-shell target is derived from the volume ignition scheme, which decouples the radiation ablation and implosion compression processes, thereby improving the robustness of the implosion. However, due to the high difficulty in manufacturing the double-metal-shell target, the neutron yield in the initial experiments was much lower than expected from simulations. To address this issue, two key improvements are proposed: first, optimizing the joint design of the outer shell to reduce the impact of hydrodynamic instability, thus to improve the collision efficiency of the inner and outer shells and the implosion efficiency of the inner core; second, enhancing the coupling efficiency of the hohlraum-target to improve the effective transfer of laser energy. With these improvements, the compression performance and implosion efficiency of the target were significantly enhanced, resulting in a substantial increase in neutron yield, from
, Available online ,
doi: 10.11884/HPLPB202537.240326
Abstract:
Flash radiography enables the diagnosis of rapid physical processes, yet the instantaneous nature of image acquisition results in a severely limited number of projections. This study investigates uncertainty quantification methods for computed tomography (CT) image reconstruction under the typical scenario of a single projection view. Current approaches for single-view CT uncertainty quantification often adopt oversimplified physical models, assuming linearized optical path equations with Gaussian noise. To address this limitation, we derive a more realistic nonlinear reconstruction framework based on the Lambert-Beer’s law, constructing an exponential attenuation model for transmittance with an integrated Gaussian noise term. This formulation yields a nonlinear posterior probability density function, which is subsequently sampled using the Randomize-Then-Optimize (RTO) algorithm combined with Gibbs sampling. The reconstructed image and its associated uncertainty are obtained through statistical analysis of the sampled data. Numerical simulations validate the proposed method, with comparative results against conventional linearized models demonstrating its superior potential for accurate uncertainty estimation in image reconstruction.
Flash radiography enables the diagnosis of rapid physical processes, yet the instantaneous nature of image acquisition results in a severely limited number of projections. This study investigates uncertainty quantification methods for computed tomography (CT) image reconstruction under the typical scenario of a single projection view. Current approaches for single-view CT uncertainty quantification often adopt oversimplified physical models, assuming linearized optical path equations with Gaussian noise. To address this limitation, we derive a more realistic nonlinear reconstruction framework based on the Lambert-Beer’s law, constructing an exponential attenuation model for transmittance with an integrated Gaussian noise term. This formulation yields a nonlinear posterior probability density function, which is subsequently sampled using the Randomize-Then-Optimize (RTO) algorithm combined with Gibbs sampling. The reconstructed image and its associated uncertainty are obtained through statistical analysis of the sampled data. Numerical simulations validate the proposed method, with comparative results against conventional linearized models demonstrating its superior potential for accurate uncertainty estimation in image reconstruction.
, Available online ,
doi: 10.11884/HPLPB202537.240314
Abstract:
Thermal diffusion coefficient is an important parameter of optical components in high-energy and high-power laser systems, and it is related to the laser damage resistance of components. However, the measurement error of the existing thermal diffusion coefficient measurement methods is large under the condition of multi-dimensional thermal conduction. As thermal diffusion length is the basis of thermal diffusion coefficient measurement, our study used the finite element method to simulate the two-dimensional heat conduction under continuous heating of heat source, and summarized the relationship between thermal diffusion length, thermal diffusion coefficient and heating time. On this basis, it proposed a model and method for measuring two-dimensional thermal diffusion length under continuous heating of heat source. Firstly, finite element analysis was used to establish a model to simulate the relationship between thermal diffusion length and thermal diffusion coefficient in one-dimensional heat conduction, and the two models were compared with numerical analytical expressions. The feasibility of using continuous heat source and thermal diffusion length to solve the thermal diffusion coefficient was verified. The effects of heat loss, sample thickness and heat source loading time on the results were discussed. Finally, the practical measurement scheme and measures to improve the measurement accuracy were put forward. This study provides a way to measure the thermal diffusion length of materials or components conveniently and accurately, and is of great significance for fabrication of high power and high energy laser system components.
Thermal diffusion coefficient is an important parameter of optical components in high-energy and high-power laser systems, and it is related to the laser damage resistance of components. However, the measurement error of the existing thermal diffusion coefficient measurement methods is large under the condition of multi-dimensional thermal conduction. As thermal diffusion length is the basis of thermal diffusion coefficient measurement, our study used the finite element method to simulate the two-dimensional heat conduction under continuous heating of heat source, and summarized the relationship between thermal diffusion length, thermal diffusion coefficient and heating time. On this basis, it proposed a model and method for measuring two-dimensional thermal diffusion length under continuous heating of heat source. Firstly, finite element analysis was used to establish a model to simulate the relationship between thermal diffusion length and thermal diffusion coefficient in one-dimensional heat conduction, and the two models were compared with numerical analytical expressions. The feasibility of using continuous heat source and thermal diffusion length to solve the thermal diffusion coefficient was verified. The effects of heat loss, sample thickness and heat source loading time on the results were discussed. Finally, the practical measurement scheme and measures to improve the measurement accuracy were put forward. This study provides a way to measure the thermal diffusion length of materials or components conveniently and accurately, and is of great significance for fabrication of high power and high energy laser system components.
, Available online ,
doi: 10.11884/HPLPB202537.240236
Abstract:
At the initial stage of beam commissioning, the turn-by-turn beam loss signals from the electron storage ring directly display the injection and accumulation of the beam. This paper introduces the types of beam loss mechanisms and enumerates several common types of beam loss monitors and their parameters. Based on the parameters of the upgrade project of the Beijing Electron Positron Collider (BEPCII) , beam loss was simulated using Geant4. The distribution of shower electrons and photons outside the vacuum chamber was analyzed. A scintillator coupled with a photomultiplier tube (PMT) monitor was chosen to detect the turn-by-turn beam loss signals. Beam tests were conducted at BEPCII, and the self-developed electronic system was used for signal acquisition and processing. To address the issue of inconsistent performance among scintillator beam loss monitors, sensitivity calibration was performed, followed by beam verification at BEPCII. This paper also introduces the signal acquisition and processing in electronics, along with the calculation and analysis of the measurement accuracy. These experiments has laid the foundation for the application of scintillation beam loss monitors in high energy photon source.
At the initial stage of beam commissioning, the turn-by-turn beam loss signals from the electron storage ring directly display the injection and accumulation of the beam. This paper introduces the types of beam loss mechanisms and enumerates several common types of beam loss monitors and their parameters. Based on the parameters of the upgrade project of the Beijing Electron Positron Collider (BEPCII) , beam loss was simulated using Geant4. The distribution of shower electrons and photons outside the vacuum chamber was analyzed. A scintillator coupled with a photomultiplier tube (PMT) monitor was chosen to detect the turn-by-turn beam loss signals. Beam tests were conducted at BEPCII, and the self-developed electronic system was used for signal acquisition and processing. To address the issue of inconsistent performance among scintillator beam loss monitors, sensitivity calibration was performed, followed by beam verification at BEPCII. This paper also introduces the signal acquisition and processing in electronics, along with the calculation and analysis of the measurement accuracy. These experiments has laid the foundation for the application of scintillation beam loss monitors in high energy photon source.
, Available online ,
doi: 10.11884/HPLPB202537.240365
Abstract:
The electron beam test platform, as a pre-research project for Shenzhen Superconducting Soft X-ray Free Electron Laser (S3FEL), will be used to overcome several major key technology challenges in high repetition frequency free electron laser. In this paper, the structural design of the injector dump beam window for the Electron Beam Test Platform of S3FEL is carried out, and a brazing water-cooled copper window is designed based on the electron beam parameters. The thermal structural calculation of the beam window is carried out using finite element analysis method, and the temperature, stress and deformation under different cooling channels and cooling water flow rates are analyzed. Considering the cooling effect, economic efficiency and flow vibration factors, the M-type cooling channel with the flow rate of 1m/s is finally selected for the beam window. In addition, the vacuum distribution at the beam window is calculated, and all the results meet the design requirements, verifying the rationality of the design and ensuring the stable and reliable operation of the facility.
The electron beam test platform, as a pre-research project for Shenzhen Superconducting Soft X-ray Free Electron Laser (S3FEL), will be used to overcome several major key technology challenges in high repetition frequency free electron laser. In this paper, the structural design of the injector dump beam window for the Electron Beam Test Platform of S3FEL is carried out, and a brazing water-cooled copper window is designed based on the electron beam parameters. The thermal structural calculation of the beam window is carried out using finite element analysis method, and the temperature, stress and deformation under different cooling channels and cooling water flow rates are analyzed. Considering the cooling effect, economic efficiency and flow vibration factors, the M-type cooling channel with the flow rate of 1m/s is finally selected for the beam window. In addition, the vacuum distribution at the beam window is calculated, and all the results meet the design requirements, verifying the rationality of the design and ensuring the stable and reliable operation of the facility.
, Available online ,
doi: 10.11884/HPLPB202537.240323
Abstract:
To explore the root cause of the reboot and shutdown phenomenon of electronic equipment in a strong electromagnetic field environment, this study considered a certain type of DC-regulated power supply as a test object and observed the susceptibility phenomena exhibited by the power supply under strong continuous wave electromagnetic radiation. In this experiment, the relative variation in voltage was selected as the effect parameter, and the variation feature of the effect parameter with the interference field strength was described. The irradiation test was carried out in the GTEM cell with an interference signal frequency range of 80–1000 MHz and a maximum field strength of 300 V/m. The test results indicate that the output voltage variation of the test power supply can be divided into two stages. When the interference field strength was low, the variation types of voltage included monotone rise, monotone fall, or first rise and then fall. At this stage, the voltage variation did not exceed 20%, and the load equipment could still operate normally. When the interference field strength was high, the voltage variation showed a sudden change. It could be divided into three types of interference phenomena such as shutting down after stopping interference (80–120 MHz, 320–350 MHz), shutting down when jamming (220–270 MHz, 360–420 MHz), rebooting (570–590 MHz, 700–720 MHz, 860–880 MHz), which posed actual threat to the load electrical equipment. There was no obvious correspondence between the susceptibility phenomena of the two stages.
To explore the root cause of the reboot and shutdown phenomenon of electronic equipment in a strong electromagnetic field environment, this study considered a certain type of DC-regulated power supply as a test object and observed the susceptibility phenomena exhibited by the power supply under strong continuous wave electromagnetic radiation. In this experiment, the relative variation in voltage was selected as the effect parameter, and the variation feature of the effect parameter with the interference field strength was described. The irradiation test was carried out in the GTEM cell with an interference signal frequency range of 80–
, Available online ,
doi: 10.11884/HPLPB202537.240350
Abstract:
Electric blasting based on electromagnetic energy equipment has great application prospects in foundation pit engineering. This article proposes the synergistic rock breaking technology based on pulse power supply and electric explosion load arrays, which achieves controllable electric blasting of large volume hard rock through the superposition of multiple shock waves. The article analyzes the mechanism of overvoltage in the process of electric explosion and the mechanism of overvoltage conduction in the multi-array collaborative process, and proposes the overvoltage suppression method. It compares the rock breaking effects of single pulse power supply and multi-array and the specific energy consumption of the dual load array is 38% of a single load for rock breaking, which indicates the electric explosion load array can effectively achieve controllable electric blasting of large volume hard rocks.
Electric blasting based on electromagnetic energy equipment has great application prospects in foundation pit engineering. This article proposes the synergistic rock breaking technology based on pulse power supply and electric explosion load arrays, which achieves controllable electric blasting of large volume hard rock through the superposition of multiple shock waves. The article analyzes the mechanism of overvoltage in the process of electric explosion and the mechanism of overvoltage conduction in the multi-array collaborative process, and proposes the overvoltage suppression method. It compares the rock breaking effects of single pulse power supply and multi-array and the specific energy consumption of the dual load array is 38% of a single load for rock breaking, which indicates the electric explosion load array can effectively achieve controllable electric blasting of large volume hard rocks.
, Available online ,
doi: 10.11884/HPLPB202537.240374
Abstract:
Traditionally, bulky external vacuum pumps are used to obtain and maintain vacuum state of the high power microwave system, which significantly increase the size and weight of the system, and limit its practical application. To achieve lightweight and miniaturization of the high power microwave system and improve its practicality, a vacuum-sealed device is designed for X-band repetitively pulsed high power microwave system. Ceramic-metal brazing technology is used at the interface between the pulse transmission line and diode, as well as between the horn mouth of the microwave antenna and the air, while knife-edge sealing technology is used at other interfaces of the system, thus to achieve vacuum packaging inside the high power microwave generation, transmission, and emission cavity. By using methods of vacuum acquisition in the field of vacuum electronics, such as material surface cleaning and baking, the system can maintain a pressure of the order of 10−7 Pa for nearly 100 h in non-operating conditions. The non-evaporable getter pumps are installed on the cylinder of the diode and the horn of the microwave antenna, which can effectively capture the gas released in the cavity when the system is powered up and maintain vacuum dynamically. The experimental results show that the system can run more than 10 000 shots stably at the pulse repetition frequency of 10-30 Hz.
Traditionally, bulky external vacuum pumps are used to obtain and maintain vacuum state of the high power microwave system, which significantly increase the size and weight of the system, and limit its practical application. To achieve lightweight and miniaturization of the high power microwave system and improve its practicality, a vacuum-sealed device is designed for X-band repetitively pulsed high power microwave system. Ceramic-metal brazing technology is used at the interface between the pulse transmission line and diode, as well as between the horn mouth of the microwave antenna and the air, while knife-edge sealing technology is used at other interfaces of the system, thus to achieve vacuum packaging inside the high power microwave generation, transmission, and emission cavity. By using methods of vacuum acquisition in the field of vacuum electronics, such as material surface cleaning and baking, the system can maintain a pressure of the order of 10−7 Pa for nearly 100 h in non-operating conditions. The non-evaporable getter pumps are installed on the cylinder of the diode and the horn of the microwave antenna, which can effectively capture the gas released in the cavity when the system is powered up and maintain vacuum dynamically. The experimental results show that the system can run more than 10 000 shots stably at the pulse repetition frequency of 10-30 Hz.
, Available online ,
doi: 10.11884/HPLPB202537.240274
Abstract:
This paper investigates the application of waveguide slot array antennas in high-power microwave technology and proposes a novel design method, with particular emphasis on the slot coupling, sidelobe levels, and matching between the antenna and the feed. The new method leverages modern computing technology to rapidly compute the slot conductance function considering slot coupling effects, thereby enabling efficient design of waveguide slot array antennas. This method avoids complex calculations or external structures, ensuring system compactness and demonstrating high effectiveness in designing waveguide slot planar arrays. Simulation results indicate that antennas designed using the new method exhibit excellent matching performance. At the center frequency f = 2.458 GHz, the reflection coefficient for each port of antenna designed using the new method ranges from −37.2 dB to −27.7 dB. Compared with the range from −11 dB to −8.7 dB of antennas designed using the Stevenson formula for the same target parameters, the reflection coefficient of antennas designed with the new method is reduced by at least 19 dB. Moreover, the antennas designed with this new method achieve a low sidelobe level of −30.2 dB and a high power capacity of 332.6 MW.
This paper investigates the application of waveguide slot array antennas in high-power microwave technology and proposes a novel design method, with particular emphasis on the slot coupling, sidelobe levels, and matching between the antenna and the feed. The new method leverages modern computing technology to rapidly compute the slot conductance function considering slot coupling effects, thereby enabling efficient design of waveguide slot array antennas. This method avoids complex calculations or external structures, ensuring system compactness and demonstrating high effectiveness in designing waveguide slot planar arrays. Simulation results indicate that antennas designed using the new method exhibit excellent matching performance. At the center frequency f = 2.458 GHz, the reflection coefficient for each port of antenna designed using the new method ranges from −37.2 dB to −27.7 dB. Compared with the range from −11 dB to −8.7 dB of antennas designed using the Stevenson formula for the same target parameters, the reflection coefficient of antennas designed with the new method is reduced by at least 19 dB. Moreover, the antennas designed with this new method achieve a low sidelobe level of −30.2 dB and a high power capacity of 332.6 MW.
, Available online ,
doi: 10.11884/HPLPB202537.240319
Abstract:
This paper presents the design of a D-dot monitor for measuring nanosecond high voltage pulses, including the design, simulation, and experiments of the probe and integrator. The electrode of the probe can be replaced and its axial length can be adjusted according to different measurement requirements. The structure of the probe is optimized according to the results of simulation on electrostatic field by CST. The amplitude-frequency response of the monitor is simulated by Pspice to ensure that the operating frequency of the monitor meets the design requirements. The D-dot monitor is applied to measure the high voltage pulses with nanosecond level pulse width. The experimental results show that the D-dot monitor meets the measurement requirements for high voltage pulses with rise time of about 37 ns and voltage amplitude of about 597 kV.
This paper presents the design of a D-dot monitor for measuring nanosecond high voltage pulses, including the design, simulation, and experiments of the probe and integrator. The electrode of the probe can be replaced and its axial length can be adjusted according to different measurement requirements. The structure of the probe is optimized according to the results of simulation on electrostatic field by CST. The amplitude-frequency response of the monitor is simulated by Pspice to ensure that the operating frequency of the monitor meets the design requirements. The D-dot monitor is applied to measure the high voltage pulses with nanosecond level pulse width. The experimental results show that the D-dot monitor meets the measurement requirements for high voltage pulses with rise time of about 37 ns and voltage amplitude of about 597 kV.
, Available online ,
doi: 10.11884/HPLPB202537.240340
Abstract:
The complexity of unmanned aerial vehicle (UAV) systems and the diversity of their fault modes present significant challenges to their reliability, stability, and safety. To address the issue of incomplete fault UAV data samples, a fault simulation dataset was constructed using a predefined fault injection method. This dataset is based on four models of faults: bias faults, drift faults, lock faults, and scale faults, allowing equivalent simulation of the drone in fault-free states, actuator failures, and sensor failures. Furthermore, the dataset was evaluated using deep learning networks. Simulation results demonstrate that the three deep learning architectures—WDCNN, ResNet, and QCNN—validate the completeness and effectiveness of the construction method and the fault simulation dataset in this paper. In terms of precision, WDCNN achieved over 82%, ResNet exceeded 90%, and QCNN surpassed 92%. The methods proposed in this study provides a complete dataset and evaluation method for data-driven research on UAV fault diagnosis.
The complexity of unmanned aerial vehicle (UAV) systems and the diversity of their fault modes present significant challenges to their reliability, stability, and safety. To address the issue of incomplete fault UAV data samples, a fault simulation dataset was constructed using a predefined fault injection method. This dataset is based on four models of faults: bias faults, drift faults, lock faults, and scale faults, allowing equivalent simulation of the drone in fault-free states, actuator failures, and sensor failures. Furthermore, the dataset was evaluated using deep learning networks. Simulation results demonstrate that the three deep learning architectures—WDCNN, ResNet, and QCNN—validate the completeness and effectiveness of the construction method and the fault simulation dataset in this paper. In terms of precision, WDCNN achieved over 82%, ResNet exceeded 90%, and QCNN surpassed 92%. The methods proposed in this study provides a complete dataset and evaluation method for data-driven research on UAV fault diagnosis.
, Available online ,
doi: 10.11884/HPLPB202537.240288
Abstract:
In this paper, four typical types of high purity graphite and their titanium carbide coating modified materials were tested as anodes in high current electron beam diodes. The results show that the currents of the diodes were obviously different when the graphite anodes were under electron beam bombardment with voltage 860 kV, current 11 kA and pulse width 40 ns. The current curve for graphite 4# was normal even after interaction of 167 electron pulses while the other graphite current curves showed different degrees of tail erosion. The ablative experiments of titanium carbide coating on graphite further verified the difference of the graphite, indicating that the thermal conductivity of graphite has an important effect on its ablative resistance. The higher the thermal conductivity of graphite, the lower the degree of recrystallization of titanium carbide, the better the corrosion resistance of graphite. Therefore, graphite 4# has an excellent resistance to electron beam bombardment and would be promising for application as collector materials in relativistic traveling wave tubes.
In this paper, four typical types of high purity graphite and their titanium carbide coating modified materials were tested as anodes in high current electron beam diodes. The results show that the currents of the diodes were obviously different when the graphite anodes were under electron beam bombardment with voltage 860 kV, current 11 kA and pulse width 40 ns. The current curve for graphite 4# was normal even after interaction of 167 electron pulses while the other graphite current curves showed different degrees of tail erosion. The ablative experiments of titanium carbide coating on graphite further verified the difference of the graphite, indicating that the thermal conductivity of graphite has an important effect on its ablative resistance. The higher the thermal conductivity of graphite, the lower the degree of recrystallization of titanium carbide, the better the corrosion resistance of graphite. Therefore, graphite 4# has an excellent resistance to electron beam bombardment and would be promising for application as collector materials in relativistic traveling wave tubes.
, Available online ,
doi: 10.11884/HPLPB202436.240163
Abstract:
The quantitative study of combat effectiveness index is crucial for the informatization construction of the armed forces. To solve the problems of limits of quantitative research, low method accuracy, and weak robustness in the study of combat effectiveness index, and to break through the limitations of dominating complex rules, multivariate mathematical models, and strong coupling of influencing factors in the combat effectiveness index function, inspired by the mathematical analysis methods of rules in fuzzy logic theory, we proposed a local approximation based method for fitting combat effectiveness index function. Combining the powerful self-learning and self-deduction capabilities of neural networks, we constructed a corresponding quantitative calculation model based on radial basis function (RBF). Simulation comparative experiments show that the proposed method has an error rate of about 2% and 6% lower than the current best performing method using global approximation, and exhibits stronger robustness. Our method has strong practicality, can be migrated to other military fields, and has good engineering application prospects.
The quantitative study of combat effectiveness index is crucial for the informatization construction of the armed forces. To solve the problems of limits of quantitative research, low method accuracy, and weak robustness in the study of combat effectiveness index, and to break through the limitations of dominating complex rules, multivariate mathematical models, and strong coupling of influencing factors in the combat effectiveness index function, inspired by the mathematical analysis methods of rules in fuzzy logic theory, we proposed a local approximation based method for fitting combat effectiveness index function. Combining the powerful self-learning and self-deduction capabilities of neural networks, we constructed a corresponding quantitative calculation model based on radial basis function (RBF). Simulation comparative experiments show that the proposed method has an error rate of about 2% and 6% lower than the current best performing method using global approximation, and exhibits stronger robustness. Our method has strong practicality, can be migrated to other military fields, and has good engineering application prospects.
Display Method:
2025, 37: 021001.
doi: 10.11884/HPLPB202537.240261
Abstract:
Photocathode electron sources play a crucial role in advanced accelerator facilities. Recent advancements in electron accelerator facilities have continually pushed the parameter boundaries of electron sources, which in turn necessitate photocathode drive lasers that possess high power, high stability, and the ability to control spatiotemporal distributions. For such a purpose, lots of efforts have been made to achieve high-quality amplification, harmonic generation, and spatiotemporal shaping of the drive laser systems. This paper presents a comprehensive review of the primary technological approaches and status of drive lasers for high-brightness electron sources worldwide. Analysis of representative drive laser schemes and discussion on the future trends are also included, aiming to provide a helpful reference for planning and developing high-performance photocathode drive laser system.
Photocathode electron sources play a crucial role in advanced accelerator facilities. Recent advancements in electron accelerator facilities have continually pushed the parameter boundaries of electron sources, which in turn necessitate photocathode drive lasers that possess high power, high stability, and the ability to control spatiotemporal distributions. For such a purpose, lots of efforts have been made to achieve high-quality amplification, harmonic generation, and spatiotemporal shaping of the drive laser systems. This paper presents a comprehensive review of the primary technological approaches and status of drive lasers for high-brightness electron sources worldwide. Analysis of representative drive laser schemes and discussion on the future trends are also included, aiming to provide a helpful reference for planning and developing high-performance photocathode drive laser system.
2025, 37: 021002.
doi: 10.11884/HPLPB202537.240209
Abstract:
Compared with vacuum tank system, supersonic injection technology has significant advantages in pressure recovery of chemical laser weapons, among them, the supersonic center injector has greater injection potential due to its smaller total pressure loss. Simulation and experimental studies were conducted on the supersonic center injector. The results show that for the supersonic center injector with a contraction-type mixing chamber, although it is easier to reach the working state, it is not superior to the straight-type injector under the condition of fixed injection coefficient and maintaining a lower blind cavity pressure. Under the condition of variable injection coefficient (fixed secondary mass flow rate), for every 0.05 increase in the area contraction ratio of the mixing chamber, the primary mass flow rate needs to be increased by approximately 0.3 kg/s to reach the critical start-up state. The overall injection performance of the supersonic injector reaches its highest when it is at the critical start-up state. In terms of blind cavity extraction capability, the single-stage supersonic center injector is significantly superior to other types of injectors, with a minimum of 1.3 kPa achievable.
Compared with vacuum tank system, supersonic injection technology has significant advantages in pressure recovery of chemical laser weapons, among them, the supersonic center injector has greater injection potential due to its smaller total pressure loss. Simulation and experimental studies were conducted on the supersonic center injector. The results show that for the supersonic center injector with a contraction-type mixing chamber, although it is easier to reach the working state, it is not superior to the straight-type injector under the condition of fixed injection coefficient and maintaining a lower blind cavity pressure. Under the condition of variable injection coefficient (fixed secondary mass flow rate), for every 0.05 increase in the area contraction ratio of the mixing chamber, the primary mass flow rate needs to be increased by approximately 0.3 kg/s to reach the critical start-up state. The overall injection performance of the supersonic injector reaches its highest when it is at the critical start-up state. In terms of blind cavity extraction capability, the single-stage supersonic center injector is significantly superior to other types of injectors, with a minimum of 1.3 kPa achievable.
2025, 37: 021003.
doi: 10.11884/HPLPB202537.240290
Abstract:
In development of high-energy chemical laser, the research of diffuser pressure recovery has important engineering application value. In this paper, the diffuser of DF chemical laser is studied by numerical simulation and experiment. The effects of diffuser divergence angle and secondary-throat on diffuser performance are calculated, analyzed and verified by experiments. The results show that the diffuser with 8° divergence angle has weak ability to resist back pressure, and reducing the divergence angle to 5° can effectively improve the ability to resist back pressure. The further optimized supersonic diffuser with secondary-throat can increase the recovery pressure of the diffuser again, reduce the energy loss of the air flow and improve the anti-back pressure characterisitics. At the same time, experimental verification is carried out for different models of diffusers, and the result is consistent with the trend of numerical simulation results.
In development of high-energy chemical laser, the research of diffuser pressure recovery has important engineering application value. In this paper, the diffuser of DF chemical laser is studied by numerical simulation and experiment. The effects of diffuser divergence angle and secondary-throat on diffuser performance are calculated, analyzed and verified by experiments. The results show that the diffuser with 8° divergence angle has weak ability to resist back pressure, and reducing the divergence angle to 5° can effectively improve the ability to resist back pressure. The further optimized supersonic diffuser with secondary-throat can increase the recovery pressure of the diffuser again, reduce the energy loss of the air flow and improve the anti-back pressure characterisitics. At the same time, experimental verification is carried out for different models of diffusers, and the result is consistent with the trend of numerical simulation results.
2025, 37: 021004.
doi: 10.11884/HPLPB202537.240216
Abstract:
In the process of high energy and high power extreme ultraviolet (EUV) irradiation, carbon deposition and surface oxidation are easy to form on the surface of the EUV mirror, which will affect its reflectivity and shorten its service life. To solve this problem, technology of nitride and oxide capping coating on the surface of extreme ultraviolet multilayer film was studied experimentally and characterized. In the preparation process, based on DC reactive magnetron sputtering coating technology, the “hyperbola” relationship between process gas flow and sputtering voltage was studied, to optimize the control of the amount of reactive gas, and then reduce the influence of reactive gas on Mo/Si multilayer films during reactive sputtering. Based on this method, TiN, ZrN and TiO2 capping layer were plated on the surface of Mo/Si multilayer films and were characterized by grazing incident X-ray reflection (GIXR), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). It is proved that the nitride capping layer has certain performance advantages.
In the process of high energy and high power extreme ultraviolet (EUV) irradiation, carbon deposition and surface oxidation are easy to form on the surface of the EUV mirror, which will affect its reflectivity and shorten its service life. To solve this problem, technology of nitride and oxide capping coating on the surface of extreme ultraviolet multilayer film was studied experimentally and characterized. In the preparation process, based on DC reactive magnetron sputtering coating technology, the “hyperbola” relationship between process gas flow and sputtering voltage was studied, to optimize the control of the amount of reactive gas, and then reduce the influence of reactive gas on Mo/Si multilayer films during reactive sputtering. Based on this method, TiN, ZrN and TiO2 capping layer were plated on the surface of Mo/Si multilayer films and were characterized by grazing incident X-ray reflection (GIXR), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). It is proved that the nitride capping layer has certain performance advantages.
2025, 37: 021005.
doi: 10.11884/HPLPB202537.240347
Abstract:
This paper introduces the overall layout of the Free Electron Laser & High Magnetic Field device under construction at Anhui University, and analyzes in detail the design requirements and difficulties in development of the water-cooling system for stable operation of the device, and presents the design of the water-cooling system for the whole device. The water-cooling system contains two independent water-cooling unit systems, with the design temperatures of (42±0.1)℃ and (25±0.5)℃ respectively, which can be adjusted within a certain range. The device water-cooling control system is developed based on EPICS (Experimental Physics and Industrial Control System) framework, the temperature regulation control function is realized by PLC (Programmable Logic Controller) program, and the PID (Proportion Integration Differentiation) parameter configuration is realized by PID regulator. The software development of the control system is mainly to realize the setting of the device parameters and the reading back of the status data under the EPICS environment, and to store the historical data into the Archiver Appliances database. The temperature control accuracy of the water-cooling control system during the trial operation reaches (42±0.03)℃ and (25±0.08)℃, which is in line with the design requirements, and the system is stable and reliable during the operation, which can well guarantee the safe and stable operation of the device.
This paper introduces the overall layout of the Free Electron Laser & High Magnetic Field device under construction at Anhui University, and analyzes in detail the design requirements and difficulties in development of the water-cooling system for stable operation of the device, and presents the design of the water-cooling system for the whole device. The water-cooling system contains two independent water-cooling unit systems, with the design temperatures of (42±0.1)℃ and (25±0.5)℃ respectively, which can be adjusted within a certain range. The device water-cooling control system is developed based on EPICS (Experimental Physics and Industrial Control System) framework, the temperature regulation control function is realized by PLC (Programmable Logic Controller) program, and the PID (Proportion Integration Differentiation) parameter configuration is realized by PID regulator. The software development of the control system is mainly to realize the setting of the device parameters and the reading back of the status data under the EPICS environment, and to store the historical data into the Archiver Appliances database. The temperature control accuracy of the water-cooling control system during the trial operation reaches (42±0.03)℃ and (25±0.08)℃, which is in line with the design requirements, and the system is stable and reliable during the operation, which can well guarantee the safe and stable operation of the device.
2025, 37: 022001.
doi: 10.11884/HPLPB202537.240199
Abstract:
In laser-driven inertial confinement fusion experiments, the CR-39 detector, a commonly-used recording medium for proton energy spectrum diagnosis, has timeliness and consistency flaws in energy spectrum measurement. However, the Timepix detector with the ability to obtain online signals can overcome these problems. To apply the Timepix detector to detect implosion proton energy spectra, it is essential to study the response of the Timepix detector to proton energies and incident angles. This work analyzes the response of the Timepix detector to proton beams in different energies and incident angles within the Allpix2 framework using Monte Carlo methods. The simulation results show that the response of the Timepix detector to proton beams in different energies and incident angles exhibits significant differences in cluster morphology, cluster size distribution, and cluster charge distribution. When incident proton beam energy is below 6 MeV, the Timepix detector exhibits high detection efficiency, and the angle of proton incidence does not significantly affect the energy response of the detector.
In laser-driven inertial confinement fusion experiments, the CR-39 detector, a commonly-used recording medium for proton energy spectrum diagnosis, has timeliness and consistency flaws in energy spectrum measurement. However, the Timepix detector with the ability to obtain online signals can overcome these problems. To apply the Timepix detector to detect implosion proton energy spectra, it is essential to study the response of the Timepix detector to proton energies and incident angles. This work analyzes the response of the Timepix detector to proton beams in different energies and incident angles within the Allpix2 framework using Monte Carlo methods. The simulation results show that the response of the Timepix detector to proton beams in different energies and incident angles exhibits significant differences in cluster morphology, cluster size distribution, and cluster charge distribution. When incident proton beam energy is below 6 MeV, the Timepix detector exhibits high detection efficiency, and the angle of proton incidence does not significantly affect the energy response of the detector.
2025, 37: 022002.
doi: 10.11884/HPLPB202537.240247
Abstract:
CUP-VISAR system is a new technology that combines Compressed Ultrafast Photography (CUP) with two-dimensional Velocity Interferometer System for Any Reflector (VISAR). To solve the problem that the image reconstruction quality of CUP-VISAR system decreases obviously under the condition of large noise, a compressed ultrafast photography reconstruction method based on iteration-interframe dual prediction is proposed. Using this method, the correlation of inter-frame image data and the correlation of iterations before and after the same frame image are studied. The compressed image reconstruction problem is presented as an iteration-inter frame dual prediction optimization problem based on Kalman prediction and inter-frame prediction, and the Plug-and-Play Generalized Alternating Projection (PnP-GAP) framework is used to solve the optimization problem effectively. Simulation results show that the minimum Peak Signal-to-Noise Ratio (PSNR) and minimum Structure Similarity Index Measure (SSIM) of the proposed method are increased by 3.18−2.11 dB and 20.30%−8.22% under large Gaussian noise conditions. The practical results show that the proposed method can obtain higher definition of fringe image, and the reconstructed line-VISAR (1D-VISAR) fringe movement trend is clearer, which verifies the effectiveness of the algorithm.
CUP-VISAR system is a new technology that combines Compressed Ultrafast Photography (CUP) with two-dimensional Velocity Interferometer System for Any Reflector (VISAR). To solve the problem that the image reconstruction quality of CUP-VISAR system decreases obviously under the condition of large noise, a compressed ultrafast photography reconstruction method based on iteration-interframe dual prediction is proposed. Using this method, the correlation of inter-frame image data and the correlation of iterations before and after the same frame image are studied. The compressed image reconstruction problem is presented as an iteration-inter frame dual prediction optimization problem based on Kalman prediction and inter-frame prediction, and the Plug-and-Play Generalized Alternating Projection (PnP-GAP) framework is used to solve the optimization problem effectively. Simulation results show that the minimum Peak Signal-to-Noise Ratio (PSNR) and minimum Structure Similarity Index Measure (SSIM) of the proposed method are increased by 3.18−2.11 dB and 20.30%−8.22% under large Gaussian noise conditions. The practical results show that the proposed method can obtain higher definition of fringe image, and the reconstructed line-VISAR (1D-VISAR) fringe movement trend is clearer, which verifies the effectiveness of the algorithm.
2025, 37: 023001.
doi: 10.11884/HPLPB202537.240399
Abstract:
The system-level cable coupling characteristics of UAVs are of great significance for the analysis of electromagnetic effects and mechanisms of UAVs. A field-circuit co-simulation model for electromagnetic interference of the multi-typed cables in UAVs is established and the coupling characteristics of the cables are analyzed. Moreover, considering the complex physical structure of the UAVs, studies on the system level cable coupling characteristics of the UAVs are carried out. Based on the surface current distribution of the UAV system, voltage monitoring points are set up at the UAV flight control port cables, wing cables, and rotor cables to monitor the voltage distribution of the UAV system cables, thus the weak links of the UAV system cable coupling are obtained. The simulation results show that when the plane wave is incident into the same length of cable at different angles, the coupling peak voltage is the largest when the electric field vector is parallel to the direction of the cable, and the coupling sensitive frequency point of different types of cables is the same; when the plane wave incident into different lengths of cable at the same angle, the reciprocals of the resonant frequency points satisfy the same multiple relationship as the cable lengths. In the actual UAV system cable irradiation scenario, the sensitive frequency band of flight control cable coupling is 300-600 MHz. The sensitive frequency band of the coupling of the UAV wing cable and the rotor cable is 300-430 MHz, and the peak voltage of the coupling of the flight control cable is significantly greater than that of the wing cable and the rotor cable.
The system-level cable coupling characteristics of UAVs are of great significance for the analysis of electromagnetic effects and mechanisms of UAVs. A field-circuit co-simulation model for electromagnetic interference of the multi-typed cables in UAVs is established and the coupling characteristics of the cables are analyzed. Moreover, considering the complex physical structure of the UAVs, studies on the system level cable coupling characteristics of the UAVs are carried out. Based on the surface current distribution of the UAV system, voltage monitoring points are set up at the UAV flight control port cables, wing cables, and rotor cables to monitor the voltage distribution of the UAV system cables, thus the weak links of the UAV system cable coupling are obtained. The simulation results show that when the plane wave is incident into the same length of cable at different angles, the coupling peak voltage is the largest when the electric field vector is parallel to the direction of the cable, and the coupling sensitive frequency point of different types of cables is the same; when the plane wave incident into different lengths of cable at the same angle, the reciprocals of the resonant frequency points satisfy the same multiple relationship as the cable lengths. In the actual UAV system cable irradiation scenario, the sensitive frequency band of flight control cable coupling is 300-600 MHz. The sensitive frequency band of the coupling of the UAV wing cable and the rotor cable is 300-430 MHz, and the peak voltage of the coupling of the flight control cable is significantly greater than that of the wing cable and the rotor cable.
2025, 37: 023002.
doi: 10.11884/HPLPB202537.240225
Abstract:
High power microwave is easy to enter the system through the main coupling path of interconnection cables between electronic devices, disrupting or even damaging sensitive circuits or devices. To guide the rational wiring in engineering and improve the survival ability of electronic system under high power microwave, the coupling effect between HPM and cable under different parameters (cable length, height from ground, terminal load resistance, radiation field incidence angle) is systematically studied by combining simulation analysis and test verification. The coupling response law is obtained and the internal reasons are analyzed. The results show that with the increase of cable length, the coupling signal oscillates first and then tends to be stable gradually, and the oscillation period is equal to the wavelength of the incident wave. The coupling signal oscillates with the change of the height from the cable to the ground, and the maximum and minimum values appear when the height from the ground is odd times of 1/4 wavelength and integer times of 1/2 wavelength of the incident wave respectively. The coupling signal decreases first and then increases with the increase of terminal load resistance. When the load resistance matches the cable characteristic impedance, the coupling signal is the smallest. The coupling signal increases with the increase of the angle between the incoming wave direction and the cable layout direction, and the coupling signal is the largest when the two are perpendicular. On this basis, some optimization suggestions of cable laying in practical engineering are given, which provides guidance for system-level electromagnetic compatibility and high-power microwave protection design.
High power microwave is easy to enter the system through the main coupling path of interconnection cables between electronic devices, disrupting or even damaging sensitive circuits or devices. To guide the rational wiring in engineering and improve the survival ability of electronic system under high power microwave, the coupling effect between HPM and cable under different parameters (cable length, height from ground, terminal load resistance, radiation field incidence angle) is systematically studied by combining simulation analysis and test verification. The coupling response law is obtained and the internal reasons are analyzed. The results show that with the increase of cable length, the coupling signal oscillates first and then tends to be stable gradually, and the oscillation period is equal to the wavelength of the incident wave. The coupling signal oscillates with the change of the height from the cable to the ground, and the maximum and minimum values appear when the height from the ground is odd times of 1/4 wavelength and integer times of 1/2 wavelength of the incident wave respectively. The coupling signal decreases first and then increases with the increase of terminal load resistance. When the load resistance matches the cable characteristic impedance, the coupling signal is the smallest. The coupling signal increases with the increase of the angle between the incoming wave direction and the cable layout direction, and the coupling signal is the largest when the two are perpendicular. On this basis, some optimization suggestions of cable laying in practical engineering are given, which provides guidance for system-level electromagnetic compatibility and high-power microwave protection design.
2025, 37: 023003.
doi: 10.11884/HPLPB202537.240228
Abstract:
To assess the susceptibility of road vehicles in complex electromagnetic environments, this paper proposes a radiation immunity testing method of vehicles based on actual electromagnetic environments in reverberation chambers (RCs), which records the actual electromagnetic signals, constructs a complex signal playback system in an RC, and gives the cumulative distribution function (CDF) of the received power. Moreover, this paper provides a field strength calibration method and the radiation immunity testing in an RC. The radiation immunity testing of vehicle was conducted, and the results show that in the complex RC electromagnetic environment, some vehicles have electromagnetic safety risks. The study method provides important support for enterprises to evaluate the electromagnetic compatibility quality of vehicles.
To assess the susceptibility of road vehicles in complex electromagnetic environments, this paper proposes a radiation immunity testing method of vehicles based on actual electromagnetic environments in reverberation chambers (RCs), which records the actual electromagnetic signals, constructs a complex signal playback system in an RC, and gives the cumulative distribution function (CDF) of the received power. Moreover, this paper provides a field strength calibration method and the radiation immunity testing in an RC. The radiation immunity testing of vehicle was conducted, and the results show that in the complex RC electromagnetic environment, some vehicles have electromagnetic safety risks. The study method provides important support for enterprises to evaluate the electromagnetic compatibility quality of vehicles.
2025, 37: 023004.
doi: 10.11884/HPLPB202537.240310
Abstract:
To solve the problem of hard connection in waveguide transmission line, some waveguide components will use flexible waveguide, but the use of flexible waveguide will bring about the increase of transmission line loss. Aiming to investigate its loss and electrical heating under real operating conditions, we built a test platform based on a resonant ring with a 13.4 dB power gain in the traveling wave of the resonant ring, which successfully achieves an equivalent power of 140 kW at the position of the antinode by means of two 2 kW power amplifiers. Based on the results of simulations and experiments, we optimized the design of the rectangular flexible waveguide and improved its structure and materials to better cope with the thermal deformation and stress under high power input. The optimized flexible waveguide's electrical and thermal performance is better than that of similar foreign products.
To solve the problem of hard connection in waveguide transmission line, some waveguide components will use flexible waveguide, but the use of flexible waveguide will bring about the increase of transmission line loss. Aiming to investigate its loss and electrical heating under real operating conditions, we built a test platform based on a resonant ring with a 13.4 dB power gain in the traveling wave of the resonant ring, which successfully achieves an equivalent power of 140 kW at the position of the antinode by means of two 2 kW power amplifiers. Based on the results of simulations and experiments, we optimized the design of the rectangular flexible waveguide and improved its structure and materials to better cope with the thermal deformation and stress under high power input. The optimized flexible waveguide's electrical and thermal performance is better than that of similar foreign products.
2025, 37: 023005.
doi: 10.11884/HPLPB202537.240338
Abstract:
The matching theory based on an equivalent circuit model is outlined that self-consistently determines the modulation of a klystron output cavity for arbitrary coupling of the output waveguide to the cavity and arbitrary cavity and/or electron beam parameters. An equivalent circuit model including a mutual inductance and the induced current for the output cavity is established, the output power and the reflected power are discussed. For the cases where the complex coupling coefficient equals 1 and does not equal 1, we respectively determined expressions for the reflected power. We derived an expression for the output power corresponding to the gap voltage for the case when the coupling is perfectly matched to the output waveguide, and also for the case of arbitrary coupling. We worked out expressions for the resonant frequency of the output cavity and externally-loaded Q leading to the matching conditions. If the matching conditions are satisfied, the output power corresponding to the new theory equals approximately the output power corresponding to the traditional theory.
The matching theory based on an equivalent circuit model is outlined that self-consistently determines the modulation of a klystron output cavity for arbitrary coupling of the output waveguide to the cavity and arbitrary cavity and/or electron beam parameters. An equivalent circuit model including a mutual inductance and the induced current for the output cavity is established, the output power and the reflected power are discussed. For the cases where the complex coupling coefficient equals 1 and does not equal 1, we respectively determined expressions for the reflected power. We derived an expression for the output power corresponding to the gap voltage for the case when the coupling is perfectly matched to the output waveguide, and also for the case of arbitrary coupling. We worked out expressions for the resonant frequency of the output cavity and externally-loaded Q leading to the matching conditions. If the matching conditions are satisfied, the output power corresponding to the new theory equals approximately the output power corresponding to the traditional theory.
2025, 37: 024001.
doi: 10.11884/HPLPB202537.240154
Abstract:
In large current accelerator beam tubes, high-frequency fields are generated when charged particles circulate within the beam pipe. To mitigate the impact on beam current, it is essential to use high-order mode damper to convert the high field energy into heat, which can then be dissipated by a cooling system. This paper presents the research, fabrication, and key performance characteristics of a hybrid high-order mode damper. The absorbing materials utilized in the damper include ferrite and silicon carbide, which can be welded to metal substrates through metallization and welding techniques. Microwave performance simulations and thermal simulations were conducted using CST and COMSOL software, respectively, leading to an optimized damper structure. Test results demonstrate that the absorption efficiency of the hybrid damper aligns closely with the calculated values in the frequency range below 1.7 GHz. However, the simulated absorption efficiency exceeds the measured results significantly above 1.7 GHz. Additionally, the vacuum leak rates, ultimate vacuum, and water resistance meet the design requirements for superconducting high-frequency cavities.
In large current accelerator beam tubes, high-frequency fields are generated when charged particles circulate within the beam pipe. To mitigate the impact on beam current, it is essential to use high-order mode damper to convert the high field energy into heat, which can then be dissipated by a cooling system. This paper presents the research, fabrication, and key performance characteristics of a hybrid high-order mode damper. The absorbing materials utilized in the damper include ferrite and silicon carbide, which can be welded to metal substrates through metallization and welding techniques. Microwave performance simulations and thermal simulations were conducted using CST and COMSOL software, respectively, leading to an optimized damper structure. Test results demonstrate that the absorption efficiency of the hybrid damper aligns closely with the calculated values in the frequency range below 1.7 GHz. However, the simulated absorption efficiency exceeds the measured results significantly above 1.7 GHz. Additionally, the vacuum leak rates, ultimate vacuum, and water resistance meet the design requirements for superconducting high-frequency cavities.
2025, 37: 024002.
doi: 10.11884/HPLPB202537.240255
Abstract:
Aiming at the problems of high failure rate, difficult maintenance, poor flexibility, and dangerous manual operation of the traditional stand-alone control of the proton beam irradiation thorium target loading and unloading system under the operating environment of low radiation, large scale, and high complexity, a control method of digital twin proton beam irradiation thorium target loading and unloading system based on the redundancy of Programmable Logic Controller (PLC) is proposed. Firstly, the method adopts a multifactor coordinated control strategy such as CPU redundancy, I/O redundancy, and power supply redundancy, and enables the control system to run uninterruptedly by constructing a hardware hot-standby redundancy system and organizing, programming, and simulating a software redundancy system. Secondly, based on the architecture of “NX MCD+PLC SIM+OPC”, the control system of digital twin virtual-reality interaction is designed, and the twin model of target loading/unloading system is constructed in the virtual space for the data information in the physical space, so as to realize the unattended and continuous monitoring in the radiation environment. Finally, experiments and reliability analysis, prove that the proposed method improves the stability of this control system to 99%, which provides a new idea for the control of operating system under irradiation environment.
Aiming at the problems of high failure rate, difficult maintenance, poor flexibility, and dangerous manual operation of the traditional stand-alone control of the proton beam irradiation thorium target loading and unloading system under the operating environment of low radiation, large scale, and high complexity, a control method of digital twin proton beam irradiation thorium target loading and unloading system based on the redundancy of Programmable Logic Controller (PLC) is proposed. Firstly, the method adopts a multifactor coordinated control strategy such as CPU redundancy, I/O redundancy, and power supply redundancy, and enables the control system to run uninterruptedly by constructing a hardware hot-standby redundancy system and organizing, programming, and simulating a software redundancy system. Secondly, based on the architecture of “NX MCD+PLC SIM+OPC”, the control system of digital twin virtual-reality interaction is designed, and the twin model of target loading/unloading system is constructed in the virtual space for the data information in the physical space, so as to realize the unattended and continuous monitoring in the radiation environment. Finally, experiments and reliability analysis, prove that the proposed method improves the stability of this control system to 99%, which provides a new idea for the control of operating system under irradiation environment.
2025, 37: 024003.
doi: 10.11884/HPLPB202537.240223
Abstract:
Due to the comprehensive performance advantages, GaN-based power devices are more suitable for the future development needs of RF power amplifier modules in the space equipment such as satellite electronic systems．Therefore, the degradation of electrical characteristics and damage mechanism of the enhancement-mode Cascode structure GaN HEMT devices were studied by irradiation experiments with 5 MeV, 60 MeV and 300 MeV protons at the irradiation dose of 2×1012～1×1014 cm−2. The experimental results show that when the irradiation dose is 2×1012 cm−2, the threshold voltage of the Cascode structure GaN HEMT device is significantly reduced, the transconductance peak is negatively drifted and the peak transconductance is reduced, the saturated drain current is significantly increased, and the gate leakage current has no significant change. When the irradiation dose reaches 1×1013 cm−2, the degradation of electrical properties is inhibited and tends to saturate. It is concluded that the cascaded silicon MOSFET in the Cascode structure GaN HEMT is the internal cause of threshold voltage negative drift and drain current increase after proton irradiation. Combined with low-frequency noise test analysis, it is found that the higher the proton irradiation dose, the larger the noise power spectral density of the device, indicating that the more defects introduced by irradiation, the more serious the irradiation damage. Compared with the results of 60 MeV and 300 MeV proton irradiation, the degradation of electrical characteristics of the device after 5 MeV proton irradiation is the most serious. SRIM simulation results show that the lower the proton irradiation energy, the greater the number of vacancies (gallium vacancy is dominated), and the more significant the degradation of electrical characteristics of the device.
Due to the comprehensive performance advantages, GaN-based power devices are more suitable for the future development needs of RF power amplifier modules in the space equipment such as satellite electronic systems．Therefore, the degradation of electrical characteristics and damage mechanism of the enhancement-mode Cascode structure GaN HEMT devices were studied by irradiation experiments with 5 MeV, 60 MeV and 300 MeV protons at the irradiation dose of 2×1012～1×1014 cm−2. The experimental results show that when the irradiation dose is 2×1012 cm−2, the threshold voltage of the Cascode structure GaN HEMT device is significantly reduced, the transconductance peak is negatively drifted and the peak transconductance is reduced, the saturated drain current is significantly increased, and the gate leakage current has no significant change. When the irradiation dose reaches 1×1013 cm−2, the degradation of electrical properties is inhibited and tends to saturate. It is concluded that the cascaded silicon MOSFET in the Cascode structure GaN HEMT is the internal cause of threshold voltage negative drift and drain current increase after proton irradiation. Combined with low-frequency noise test analysis, it is found that the higher the proton irradiation dose, the larger the noise power spectral density of the device, indicating that the more defects introduced by irradiation, the more serious the irradiation damage. Compared with the results of 60 MeV and 300 MeV proton irradiation, the degradation of electrical characteristics of the device after 5 MeV proton irradiation is the most serious. SRIM simulation results show that the lower the proton irradiation energy, the greater the number of vacancies (gallium vacancy is dominated), and the more significant the degradation of electrical characteristics of the device.
2025, 37: 025001.
doi: 10.11884/HPLPB202537.240248
Abstract:
Many applications including plasma excitation and high-power microwave sources require miniaturized high-voltage pulse generators. A miniaturized Marx generator with a novel magnetic isolated drive circuit is proposed. Making the source terminals of the charging MOSFET and discharging MOSFET in adjacent stages shorted in Marx generators based on half-bridge circuits, we apply a bipolar signal to both gates of these two MOSFETs and control both their switching. Combined with magnetic isolated driver with primary windings in series, only one bipolar signal from the primary side can synchronously drive all switches in the Marx generator, which considerably reduces the number of required components in the drive circuits. A 14-level experimental prototype was built, with a total weight of only 314 g, a width of 15 cm, a length of 8 cm, and a height of 5 cm. High-voltage square wave pulses with a peak voltage of 10 kV, a repetition frequency of 10 kHz, and a pulse width ranging from 200 ns to 5 μs were obtained over a resistive load. The 500 ns, 10 kV, and 1 kHz square wave pulses generated by the prototype were used to drive the dielectric barrier discharge load, and a uniform and strong discharge was generated, indicating that the miniaturized Marx generator is suitable for driving the dielectric barrier discharge load and being used as a low-temperature plasma source.
Many applications including plasma excitation and high-power microwave sources require miniaturized high-voltage pulse generators. A miniaturized Marx generator with a novel magnetic isolated drive circuit is proposed. Making the source terminals of the charging MOSFET and discharging MOSFET in adjacent stages shorted in Marx generators based on half-bridge circuits, we apply a bipolar signal to both gates of these two MOSFETs and control both their switching. Combined with magnetic isolated driver with primary windings in series, only one bipolar signal from the primary side can synchronously drive all switches in the Marx generator, which considerably reduces the number of required components in the drive circuits. A 14-level experimental prototype was built, with a total weight of only 314 g, a width of 15 cm, a length of 8 cm, and a height of 5 cm. High-voltage square wave pulses with a peak voltage of 10 kV, a repetition frequency of 10 kHz, and a pulse width ranging from 200 ns to 5 μs were obtained over a resistive load. The 500 ns, 10 kV, and 1 kHz square wave pulses generated by the prototype were used to drive the dielectric barrier discharge load, and a uniform and strong discharge was generated, indicating that the miniaturized Marx generator is suitable for driving the dielectric barrier discharge load and being used as a low-temperature plasma source.
2025, 37: 025002.
doi: 10.11884/HPLPB202537.240334
Abstract:
Aiming at the pulse operating characteristics of voltage-controlled thyristors, a cascadable driving circuit is designed to realize the synchronous opening of multi-stage series-connected voltage-controlled thyristors. Firstly, the circuit topology and working principle is analysed. in which the coupled inductor is used to isolate the driver signal and transfer power to open the switch. Based on Blumlein PFN, an experimental test circuit is built, in which a 6-stage MOS-controlled thyristor is series connected to be the discharge switch. A quasi-square-wave pulse current with an amplitude of 1.958 kA is obtained on a 4 Ω resistor.
Aiming at the pulse operating characteristics of voltage-controlled thyristors, a cascadable driving circuit is designed to realize the synchronous opening of multi-stage series-connected voltage-controlled thyristors. Firstly, the circuit topology and working principle is analysed. in which the coupled inductor is used to isolate the driver signal and transfer power to open the switch. Based on Blumlein PFN, an experimental test circuit is built, in which a 6-stage MOS-controlled thyristor is series connected to be the discharge switch. A quasi-square-wave pulse current with an amplitude of 1.958 kA is obtained on a 4 Ω resistor.
2025, 37: 026001.
doi: 10.11884/HPLPB202537.240369
Abstract:
Fast Burst Reactors (FBRs) are important subjects for criticality safety analysis research. They are characterized by irregular geometry, strong transient processes, tight multi-physics coupling, and complex feedback characteristics. This paper introduces an OpenFOAM based multi-physics nuclear criticality safety analysis code named INSL-UniFoam. It integrates discrete ordinate neutron transport solver, heat transfer and stress-strain solvers to detailly model the prompt super-critical burst pulse of FBRs. The UniFoam is first verified in the Godiva-I benchmark under both the steady-state condition and several transient scenarios. The results demonstrate that the program aligns well with the reference solution in terms of Keff calculation, peak power, and fission yield. Furthermore, it is capable of comprehensively outputting the distributions of power, temperature, and stress-strain throughout the pulse process.
Fast Burst Reactors (FBRs) are important subjects for criticality safety analysis research. They are characterized by irregular geometry, strong transient processes, tight multi-physics coupling, and complex feedback characteristics. This paper introduces an OpenFOAM based multi-physics nuclear criticality safety analysis code named INSL-UniFoam. It integrates discrete ordinate neutron transport solver, heat transfer and stress-strain solvers to detailly model the prompt super-critical burst pulse of FBRs. The UniFoam is first verified in the Godiva-I benchmark under both the steady-state condition and several transient scenarios. The results demonstrate that the program aligns well with the reference solution in terms of Keff calculation, peak power, and fission yield. Furthermore, it is capable of comprehensively outputting the distributions of power, temperature, and stress-strain throughout the pulse process.
2025, 37: 026002.
doi: 10.11884/HPLPB202537.240307
Abstract:
The construction of the burnup lib determines the accuracy of burnup and decay heat calculations. The evaluation of burnup information in the nuclear lib is complex, leading to a large, rigid, and inefficient burnup matrix. This paper begins with the basic composition of the burnup lib, considering the impact of each nuclide and its transformation relationships on the accuracy of neutronics calculations and target nuclide nuclear density calculations, which serves as the basis for the compression of the burnup lib. To address the decay heat calculation accuracy loss caused by the compression of fission products, a nonlinear least squares optimization algorithm is used to fit the decay heat release function, and pseudo-decay nuclides are constructed to replace the fission product decay heat calculation, thereby maintaining the accuracy of decay heat calculations. Verification results show that the original detailed burnup lib contains more than 1 500 nuclides, which are reduced to fewer than 200 nuclides after compression. The compressed burnup lib does not introduce significant deviations in the calculation of the effective multiplication factor and nuclear density. In terms of decay heat calculations, the pseudo-decay nuclides significantly restore the decay heat calculation accuracy, with the contribution of decay heat to total power having a calculation deviation of less than 0.5%, meeting the required accuracy for decay heat calculations.
The construction of the burnup lib determines the accuracy of burnup and decay heat calculations. The evaluation of burnup information in the nuclear lib is complex, leading to a large, rigid, and inefficient burnup matrix. This paper begins with the basic composition of the burnup lib, considering the impact of each nuclide and its transformation relationships on the accuracy of neutronics calculations and target nuclide nuclear density calculations, which serves as the basis for the compression of the burnup lib. To address the decay heat calculation accuracy loss caused by the compression of fission products, a nonlinear least squares optimization algorithm is used to fit the decay heat release function, and pseudo-decay nuclides are constructed to replace the fission product decay heat calculation, thereby maintaining the accuracy of decay heat calculations. Verification results show that the original detailed burnup lib contains more than 1 500 nuclides, which are reduced to fewer than 200 nuclides after compression. The compressed burnup lib does not introduce significant deviations in the calculation of the effective multiplication factor and nuclear density. In terms of decay heat calculations, the pseudo-decay nuclides significantly restore the decay heat calculation accuracy, with the contribution of decay heat to total power having a calculation deviation of less than 0.5%, meeting the required accuracy for decay heat calculations.
2025, 37: 025003.
doi: 10.11884/HPLPB202537.240282
Abstract:
Double energy accelerator used in custom security monitoring is powered by the high-power magnetron, the top of pulse current waveform through the magnetron varies greatly in the double energy operation mode of the ordinary solid-state modulator due to nonlinear impedance of the magnetron, thus it is difficult to precisely distinguish contraband from the commodity in the cargo. To make the top of the pulse current waveform through the magnetron used in the double energy accelerator flat in the double energy operation mode, we developed a solid state modulator based on dual-loop parallel circuit topology, parallel IGBT solid state switch, high ratio pulse transformer technology and waveform correction technique for double energy accelerator. When the operating current through the magnetron is in the range of 70～120 A , this solid state modulator can output quasi-trapezoid current waveform in the double energy operation mode, and the relative top fluctuation of the pulse waveforms through the magnetron is less than 5%.
Double energy accelerator used in custom security monitoring is powered by the high-power magnetron, the top of pulse current waveform through the magnetron varies greatly in the double energy operation mode of the ordinary solid-state modulator due to nonlinear impedance of the magnetron, thus it is difficult to precisely distinguish contraband from the commodity in the cargo. To make the top of the pulse current waveform through the magnetron used in the double energy accelerator flat in the double energy operation mode, we developed a solid state modulator based on dual-loop parallel circuit topology, parallel IGBT solid state switch, high ratio pulse transformer technology and waveform correction technique for double energy accelerator. When the operating current through the magnetron is in the range of 70～120 A , this solid state modulator can output quasi-trapezoid current waveform in the double energy operation mode, and the relative top fluctuation of the pulse waveforms through the magnetron is less than 5%.
2025, 37: 026003.
doi: 10.11884/HPLPB202537.240150
Abstract:
This paper presents a model for aerosol inertial collision removal under mixed gas jet conditions with high Weber number, based on the hydrodynamic model of jet penetration length and entrained droplet fraction. An analysis code of the aerosol pool scrubbing is constructed by spatial discretization of the injection zone. The experimental cases are adopted to validate the model, including two cases of 64% steam fraction, 0.7 m submergence depth, and mass fluxes of 217 kg/(m2·s) and 120 kg/(m2·s), conducted by small scale aerosol pool scrubbing facility, and one Reinforced Concerted Action 2 (RCA2) experiment with non-condensable gas-carrying aerosols at 0.5 m submergence depth and mass fluxes of 95 kg/(m2·s). The results show that the predictions of the model considering the jet hydrodynamic characteristics are in good agreement with the experimental values. Parameter analysis shows that as the Weber number of immersed jet increases, both jet penetration length and entrained droplet fraction increase, thereby enhancing the inertial collision between aerosols and droplets.
This paper presents a model for aerosol inertial collision removal under mixed gas jet conditions with high Weber number, based on the hydrodynamic model of jet penetration length and entrained droplet fraction. An analysis code of the aerosol pool scrubbing is constructed by spatial discretization of the injection zone. The experimental cases are adopted to validate the model, including two cases of 64% steam fraction, 0.7 m submergence depth, and mass fluxes of 217 kg/(m2·s) and 120 kg/(m2·s), conducted by small scale aerosol pool scrubbing facility, and one Reinforced Concerted Action 2 (RCA2) experiment with non-condensable gas-carrying aerosols at 0.5 m submergence depth and mass fluxes of 95 kg/(m2·s). The results show that the predictions of the model considering the jet hydrodynamic characteristics are in good agreement with the experimental values. Parameter analysis shows that as the Weber number of immersed jet increases, both jet penetration length and entrained droplet fraction increase, thereby enhancing the inertial collision between aerosols and droplets.
