涂覆吸波材料对发动机排气系统雷达散射特性的影响

Influence of Radar Absorbing Coating Materials on Radar Scattering Characteristics ofEngine Exhaust System

中文关键词:  吸波材料  排气系统  雷达散射特性  弹跳射线法  航空发动机

英文关键词:absorbing material  exhaust system  radar scattering characteristics  shooting and bouncing rays  aeroengine

中文摘要:

      为了获取涂覆吸波材料对排气系统雷达散射特性影响的规律，拟定了3种吸波材料涂覆方案研究了3种不同吸波性能。 利用弹跳射线法仿真分析了涂覆吸波材料对排气系统在1、8、18 GHz频点，方位角在-40°～40°内水平极化与垂直极化雷达散射 截面（RCS）的影响。结果表明：吸波材料涂覆部位不同，各部件产生的散射回波在腔体中耦合、叠加形成的散射总场随之改变，导 致排气系统RCS振荡特性变化，随着雷达波频率的提高，对RCS振荡特性的影响逐渐变大；保持相同涂覆方案提高材料吸波性能， 可提高排气系统RCS缩减效果但对RCS振荡特性没有影响，将涂覆部位最多方案的材料反射率由-4 dB降至-6 dB时，在1、8、18 GHz水平极化的RCS均值缩减效果提高至89%、89%、96%，垂直极化3个频点的RCS均值缩减效果提高至85%、90%、95% 。

英文摘要:

      In order to obtain the influence of radar absorbing coating materials on radar scattering characteristics of engine exhaust system, three absorbing materials coating schemes were formulated and three different absorbing properties were studied. The influences of radar absorbing coating materials on the horizontal polarization and vertical polarization RCS of the exhaust system at frequencies of 1 GHz, 8 GHz, and 18 GHz and azimuth angles ranging from -40° to 40° were simulated and analyzed by using the shooting and bouncing rays method. The results show that with the change of coating locations of the absorbing materials, the total scattering fields formed by coupling and superposition of scattering echoes generated by various components in the cavity also change, resulting in changes of the RCS oscilla? tion characteristics of the exhaust system; with the increase of radar wave frequency, the impact on the oscillation characteristics gradually increases. While keeping the same coating scheme, improving the radar absorbing performance of the material can increase the RCS reduc? tion effect of the exhaust system without affecting the RCS oscillation characteristics. When the material reflectivity of the coating scheme with the most coating locations is reduced from -4 dB to -6 dB, the average RCS reduction effects of the horizontal polarization at 1 GHz, 8 GHz and 18 GHz are increased to 89%, 89%, and 96%, and the average RCS reduction effects of the vertical polarization of the three frequency points are increased to 85%, 90%, and 95%.