喷管类型对飞行器排气系统辐射特性的影响

Numerical Simulation of Radiation Characteristics of Aircraft Exhaust Systems with Different Nozzles

排气系统是飞行器最主要的红外辐射源,其喷管的形状类型对排气系统红外辐射强度的大小及分布有很大影响。本文建立了3种不同类型喷管的三维模型,在此基础上运用ANSYS软件模拟了各自排气系统的温度场分布,结合Curtis-Godson(C-G)谱带法对各类型喷管红外辐射特性进行了计算与对比研究。结果表明:在出口面积相同的条件下,二元矩形S弯喷管的尾焰核心区域面积最小,约为轴对称圆形喷管的60%;在矩形喷口的宽边探测面上,二元矩形S弯喷管的红外辐射强度最小。3类喷管中,二元矩形S弯喷管隐身性能最好,二元矩形喷管次之,轴对称圆形喷管最差。

The exhaust system is the most important infrared radiation source of an aircraft,and the shape of the nozzle contributes to the infrared radiation characteristics of the exhaust system.Three types of 3D nozzles were built,and the temperature field of the plume was simulated using ANSYS14.5.Then,the spectral infrared radiation characteristics of the plume were obtained using the single band Curtis-Godson(C-G)approximation method.The results show that under the same exit area,the core area of the S-shaped nozzle plume is minimum and is approximately 60%of the axisymmetric circular nozzle plume;in the rectangular nozzle wide edge detection surface,the infrared radiation of the dual rectangular nozzle is minimum,and among the three types of nozzles,the stealthy performance of the two-element rectangular S curved nozzle is the best,the two-element rectangular nozzle takes the second place,and the axial symmetrical circular nozzle is the worst.