Integrative design of nozzle, cavity and pressure recovery system

The 3-dimensional numerical simulation of nozzle and diffuser for COIL system is performed. Several nozzle and diffuser designs are compared and analzed. The gasdynamic process from cavity inlet till diffuser outlet is computated. The sufficient mixing of primary and secondary flows in cavity can be reached by means of aiding tab, which is 0.77 cm×0.254 cm. The computational model of diffuser is the 1/4 construction, of which the input cross-section is 30 mm×60 mm. After keeping the same cross-section size till the length is 500 mm, the diffuser is continued with the same width and 4° divergent angle in height till the length is 700 mm. The final output area size of diffuser is 79 mm×60 mm. The input (output of cavity) gas condition of diffuser is air with Mach number of 3.2, static pr