中心线形状对S形二元收敛喷管雷达隐身设计的影响

Impact of Centerline Shape of S-shaped Two-dimensional Convergent Nozzle on Radar Stealth Design

为了探求中心线形状对S形二元收敛喷管电磁散射特性的影响规律,在S形二元收敛喷管进出口面积、偏心距、面积变化规律不变的条件下,结合超椭圆方法设计了5种不同中心线形状变化规律的S形二元收敛喷管,采用多层快速多极子方法对上述5种喷管进行了雷达散射截面(RCS)仿真计算和分析。结果表明:5种不同中心线形状变化规律的S形二元收敛喷管在不同频率和不同极化条件下表现出不同变化规律的雷达隐身特性;综合分析中心线形状C(缓急相当)的喷管整体雷达隐身性能较好,RCS平均值最高为0.953 dBm2、最低为-1.3 dBm2;中心线形状E(前急后缓)的喷管,RCS平均值为1.6 dBm2~2.209 dBm2;中心线形状B的喷管雷达隐身性能最差,RCS平均值最高为2.71 dBm2、最低为0.081 dBm2。

To evaluate the impact of centerline shape of S-shaped two-dimensional convergent nozzle on the electromagnetic scattering characteristics,while keeping the inlet and outlet area,offset,and area variation rule unchanged,five S-shaped two-dimensional convergent nozzles with different centerline shapes were designed by adaptive hyperelliptic method,and simulation and analysis of their radar cross section(RCS) conducted using Multilevel Fast Multipole Method(MLFMM). The results show that the radar stealth characteristics of these nozzles with different centerline shapes vary under different frequencies and polarization conditions. The overall radar stealth performance of the nozzle with centerline C(modest turning at entrance and exit)is the best,with RCS average ranging from-1.3 dBm~2 to 0.953dBm~2;The second best is the nozzle with the centerline E(rapid turning at the entrance and slow turning at exit),with RCS average ranging from-2.009 dBm~2 to 1.61dBm~2,the nozzle with centerline B is the worst,with RCS average ranging from 0.08 dBm~2 to 2.71 dBm~2.