扩张型双喉道喷管的流动特性和起动方法

利用数值模拟方法,对二元扩张型双喉道喷管的流动特性和起动方法进行了研究.结果表明:扩张型双喉道喷管内会出现正激波系,产生了很大的总压损失,使第2喉道壅塞,喷管不能起动.在低落压比条件下,喉道注气可以形成大的分离区,使激波强度减弱、喷管可以起动;在大落压比条件下,喉道注气不能形成大的分离区,喷管不能起动.扩张段注气可以在喷管内形成大的分离区,使正激波转变成斜激波系,减小了总压损失,使第2喉道流通能力增强、喷管起动. 

Flow characteristic and starting method for divergent dual throat nozzle

The flow characteristic and starting method of two-dimensional divergent dual throat nozzle were studied numerically.The results show that there will be normal shock waves in the divergent zone of the dual throat nozzle,which result in great loss in total pressure and choke at the second throat,thus the nozzle can not start.In the condition of low nozzle pressure ratio,a large separation region,which weakens the shock waves,can be formed by injection in the throat,and the nozzle can start;in the condition o...