翼面隐身结构电磁散射特性的数值模拟

Numerical Simulation of Electromagnetic Scattering for Wing Structures with Low Observability

隐身结构是指由蒙皮和多种内部材料组成的、能满足承载要求、并能明显降低雷达散射截面的结构。针对某无人侦察机隐身性能的要求,设计出两种低成本的翼面隐身结构方案。但由于隐身结构由多种媒质构成,其雷达散射截面(RCS)的计算和分析是个难题。应用时域有限差分法(FDTD法)建立隐身结构电磁散射的数值模型,对两种低成本的翼面隐身结构方案的RCS进行了计算和比较分析。数值模拟结果表明,两种翼面隐身结构方案能有效降低翼面的RCS,并且翼面前、后缘和梁腹板之间填充的含有石墨的发泡聚苯乙烯对RCS值有很大影响。这一结论对隐身结构的优化设计具有指导意义。

The low observable structure is a type of the structures which consist of skin and various internal materials, and have low radar cross section （RCS） together with the considerations of their stress and other requirements. Two kinds of the low observable wing structures are designed for a low observable unmaned air vehicle. But numerical simulation of electromagnetic scattering for such wing structures is a challenging problem because the wing structures consist of different materials having different eletric and magnetic properties. The paper proposes the applications of the finite difference-time domain （FD-TD） method to the numerical simulation of electromagnetic scattering for such wing structures, and presents the simulation results of electromagnetic scattering characteristics of those kinds of the low observable wing structures. The results indicate that the RCS values of those two types of wing structures are reduced substantially compared to conventional wings, as well as the graphite-embeded foamed polystyrenes have major contribution on the RCS reduction of two wing structures. The conclusions can be used as a guidance for further reducing RCS value of the low observable structure using optimization methods.