侧喷发动机配置对目标红外辐射特性影响数值研究

Numerical study on effects of side injection engine configuration on target infrared radiation characteristics

高超声速飞行器姿控发动机侧喷射流作为目标红外“机会”辐射源在拦截弹攻防对抗领域被重点关注。文中以典型锥柱裙外形弹体为研究对象,考虑真实可压缩气体和化学非平衡效应,结合辐射平衡壁面条件预测弹体在典型飞行工况(H=20 km,Ma=5和H=50 km,Ma=10)下不同喷口配置下的侧喷流场,结合窄谱带方法处理高温气体辐射物性参数,采用视在光线法求解辐射传输方程,数值分析了侧喷发动机喷射角、喷口位置和压比配置对拦截弹侧喷射流红外辐射特性的影响。结果表明:高超声速飞行器红外辐射强度随喷射角由负转正而增大,辐射峰值增长率约为2 W/(sr·μm·°);光谱辐射强度随喷口位置后移,H=20 km下先急剧升高后缓慢降低,H=50 km下存在陡降点;红外辐射强度随射流压比的增大而增大,辐射峰值增长率约为14 W/(sr·μm)。

As the target infrared“opportunity”radiation source,the hypersonic aircraft attitude control en⁃gine side jet stream has been focused on in the field of interceptor missile offensive and defensive countermea⁃sures.The typical cone-cylindrical skirt shape projectile is taken as the research object,considering the real compressible gas and chemical non-equilibrium effects,combined with the radiation equilibrium wall surface conditions to predict the typical flight conditions of the projectile(H=20 km,Ma=5 and H=50 km,Ma=10).The side jet flow field under different nozzle configurations is shown below,combined with the narrow band method to process the radiation physical parameters of high temperature gas,and the line of sight method is used to solve the radiation transfer equation.The effects of injection angle,nozzle position,and jet pressure ratio on the infra⁃red radiation characteristics of the interceptor’s side jet flow were analyzed through numerical calculations.The results show that the infrared radiation intensity of the hypersonic vehicle increases as the injection angle changes from negative to positive,and the peak radiation growth rate is about 2 W/(sr∙μm∙°).As the nozzle position moves backward,the spectral radiation intensity at H=20 km first increases sharply and then slowly decreases,and there is a steep drop point at H=50 km.The infrared radiation intensity increases with the increase of the jet pressure ratio,and the radiation peak growth rate is about 14 W/(sr∙μm).