喷管超音段壁面排气引射冷却方案气动特性研究

在常温条件下,对3种轴对称收扩喷管超音段壁面排气引射冷却方案(缝隙式气膜冷却、离散孔式气膜冷却和冲击—气膜组合式冷却)的气动特性进行了试验研究,得到了不同冷却方案的推力系数、壁面压力分布和抽吸特性以及冷却气流量对这些性能的影响。试验结果表明:与常规轴对称收扩喷管相比,采用排气引射冷却的喷管具有更好的推力特性,3种喷管的抽吸特性都优于轴对称基准喷管。 

Aerodynamic Performance Investigation of Exhaust Nozzles with Ejector Pumping and Cooling on Divergent Wall

The aerodynamic performance of an axisymmetric convergent-divergent exhaust pumping nozzle with cooling on divergent wall was investigated.The three cooling schemes were adopted,such as slot film cooling,discrete hole film cooling and impact-film cooling.The influences of cooling air flowrate on thrust coefficients,distribution of wall pressure and pumping characteristics of nozzles for every scheme were also investigated.Compared with conventional axisymmetric nozzle,some thrust gain was obtained on the nozzle with pumping and cooling.The different cooling methods have significant effects on the distribution of wall pressure in the nozzle supersonic section.The pumping performance of the nozzle with slot cooling is best,the followed is a nozzle with impact-film cooling.Experimental results show that the proposed ejector pumping nozzle concept is superior to baseline nozzle in thrust characteristics and pumping performance .