采用时域有限差分(FDTD)方法研究了等离子体鞘套包覆目标的电磁散射特性,发展了超高速飞行器及其等离子体鞘套RCS特性并行计算软件。采用发展的软件完成了超高速开槽钝锥后向远区时域特性和0°入射角附近的电磁散射截面积(RCS)的计算分析,并在中国空气动力研究与发展中心的气动物理靶上进行了超高速开槽钝锥体的RCS验证试验。研究表明:在钝锥体表面开环槽并填充透波性能良好的介质材料相当于在钝锥体表面人为地增加了一个散射中心;在低频区和谐振区,开槽后钝锥体的RCS在原值周围变化,而在高频区,钝锥体的RCS在0°入射角附近很宽的范围内均显著增大。
The finite difference time domain (FDTD) method was used to study the RCS (radar cross section) characteristics of hypersonic vehicle and its plasma sheath. The parallel computational software was developed and used to analyze the far field time-domain baekseattering characteristic and the RCS of blunt-cone with slots while incident angle was nearby 0°. The numerical values were compared with test results which were proeessed in aero-physics ballistic range of CARDC. The results showed that while slots-encircled blunt-cone filled with medium which had well per- formanee in wave transmitting were equivalent to add a scatter center to blunt-cone artificially. The RCS in low-frequency and resonance region was not changed obviously when incident angle was nearby 0°, but in high-frequency re~ion it was increased obviously for a wide freauencv hand.