Abstract: The radar cross section (RCS) of spherical convergent flap nozzles (SCFN) with different vector angles of pitch and yaw plane were obtained by using the numerical simulation method-iteration physical optical(IPO) to study the effects of vector angle on the backward scattering characteristics. It’s calculated that the vector angle of pitch can reduce the RCS of SCFN in the both detecting plane by above 20 percent. The vector angle of yaw can only reduce about 50 percent of the RCS in the pitch plane， but increase about 150 percent of the RCS in the yaw plane. The SCFN with 15 degree vector angle in the pitch plane has the smallest RCS value.

Key words: Spherical convergent flap nozzle；Vector angle；Iteration physical optics；Radar cross section

摘要： 为了研究几何矢量角对球面收敛二元矢量喷管后向电磁散射特性的影响，采用物理光学迭代方法分别对不同俯仰矢量角和偏航矢量角下球面收敛矢量喷管的雷达截面积进行了数值模拟，得到了矢量角对于球面收敛二元矢量喷管的电磁散射特性的影响规律。研究结果表明:俯仰矢量角在两个探测平面内均可降低球面收敛二元矢量喷管的RCS20%以上，偏航矢量角只能在俯仰平面降低球面收敛二元矢量喷管RCS50%左右，在偏航平面则会增加球面收敛二元矢量喷管RCS约150%；俯仰矢量角为15°时，模型的后向RCS最小。

关键词: 球面收敛矢量喷管；矢量角；迭代物理光学；雷达散射截面积