收扩喷管加小突片对尾喷流红外辐射的影响

针对收扩喷管 ,在高温 (约 64 0℃ )、高速 (超音速 )流动状态下 ,实验研究了加装小突片后对飞机发动机尾喷流红外辐射的抑制效果 ,并探讨了小突片堵塞比、小突片后倾角度等因素对红外辐射抑制特性的影响。结果表明 ,小突片对热射流的红外辐射具有明显的抑制作用 ,不仅使热射流的核心区长度大为缩短 ,而且使热射流的总体红外辐射信号大幅度下降 (在本文实验范围内 ,最大可下降约 57% )。

Effect of Tabs Fixed on a Convergent-Divergent Nozzle on Infrared Radiation of Exhausting Jet

The effect of tabs fixed on a convergent-divergent nozzle on theinfrared radiation of the exhausting high speed (subsonic and supersonic) hot (about 640℃) jet was investigated,and the influence of tab block ratio and inclined angle on the suppression of infrared radiation was studied.The results show that tabs can cut down a good lot of hot jet core length and suppress the infrared radiation up to 57% from the hot jet.The increase in tab block ratio of 1% decreases the infrared radiation intensity of the whole hot exhausting gas by about 5.5% in average,and the increase in tab inclined angle by 1 degree can suppress the infrared radiation intensity of the whole hot exhausting gas by about 0.21% in average in the test conditions.