In view of the ejector optimization problem considering the comprehensive influence of multiple factors

based on the ejector function method

the mathematical characteristics of static pressure matching function were studied and the singular points on the mathematical curve were analyzed. On this basis

the multi branch characteristic curves were obtained by programming and benchmark progression induction method

and the characteristics of solutions under different branches were analyzed. In addition

the influences of mixing chamber back pressure

total pressure ratio of primary and secondary flow and mixing nonuniformity on the ejector performance were studied

and the design concepts of static pressure characteristic curve and critical curve were proposed. The reliability of the ejector function method was verified by comparing with the experimental data. The results showed that the design performance of the ejector was better when it was close to the critical curve. The mixing nonuniformity had a great influence on the ejector performance

when the nonuniformity was 1.5

compared with the ideal state

the maximum error of the ejecting coefficient reached 32.73%. When considering the wall friction design

the friction coefficient formula model should be modified. The results provide an important guidance for the optimal design of ejector.