基于面元边缘法的直升机RCS计算与分析

Calculation and Analysis of RCS of Helicopter Based on Panel Edge Method

针对直升机的雷达散射截面(Radar cross section,RCS)的计算特点,将物理光学法和等效电磁流法相结合,建立了一套基于"面元-边缘"的分析方法。在该方法中,首先对复杂目标(如直升机)进行几何建模和网格划分,然后通过转换程序,获取目标的拓扑结构数据文件;其次在考虑遮挡影响下,分别进行目标表面散射场和边缘绕射场的计算;最后叠加获得总的散射场。在通过球板组合和某外形结构复杂的导弹算例验证本文分析方法有效性的基础上,对某直升机分别沿方位角、俯仰角和滚转角三个方向的RCS进行了计算和分析,并研究了挂架、导弹对直升机整体RCS的影响,获得了一些减缩直升机RCS的外形设计方案。

Considering the characteristics of radar cross section（RCS） of helicopter,a panel edge method by combining the physical optics and the equivalent currents is developed.Firstly,geometric model and mesh generation for complex target（such as helicopter） are conducted,and topology data about the target are obtained by using transformation program.Secondly,by considering the effects of shadowing on RCS,calculations on panel and edge diffraction field of target are performed respectively.Then,total scattered field is obtained.By taking the combination model of sphere with plate and a complicated structure of missile as numerical examples,it shows that the method is effective to analyze the RCS of complex target.Finally,calculation and analysis of RCS of helicopter at different azimuth angle,rolling angle and pitching angle are performed,and the effects of bracket and missile on the whole RCS of helicopter are analyzed.Some shape design approaches aiming at reducing helicopter RCS are obtained.