采用低发射率涂层的发动排气系统红外特征实验

摘要

The coating with low infrared emissivity was employed to suppress the infrared radiation(IR) of axisymmetric convergent nozzle for a turbofan engine, and experimental research was conducted on the simulation test bench of turbofan engines. The infrared radiation intensity in 3～5 μm of axisymmtric convergent nozzle on the orientation of 0°, 5°, 10°, 15°, 20°, 30°, 45°, 60°, 75° and 90° on horizontal plane was measured with and without the nozzle low infrared emissivity coating. The results show that low infrared emissivity coating can reduce the IR intensity of the nozzle by about 15％. The coating can distinctly suppress the IR radiation intensity from nozzle wall but it has little effect on IR radiation intensity of gas plum.%实验测量了涡扇发动机收敛喷管排气系统模型的红外辐射强度的分布,比较了中心锥表面上涂覆低发射率涂层前后,水平平面内0°,5°,10°,15°,20°,30°,45°,60°,75°和90°方向上在3～5 μm波段的红外辐射强度.结果表明:在0°～45°范围内,中心锥表面涂覆发射率ε为0.51的涂层后排气系统的辐射强度比原型(中心锥表面ε=0.89)排气系统的红外辐射有明显下降,最大降幅约为15%;低发射率涂层对排气系统固体壁面辐射抑制作用明显,而对燃气辐射几乎没有影响.