翼剖面介质构形的隐身缩比模型数值计算研究

 结构型吸波材料以全角度、多方位的有效性和不改变飞行器原有形状设计的特点，在隐身技术领域占有重要的技术地位，开展全尺度结构的隐身效能与其技术参数影响作用的研究需要较大的测试空间与经费支持，由此限制了试验技术在更大范围内的应用。结合试验技术与参数研究的应用需求，探讨缩比介质体电磁散射规律可提供于大型结构隐身技术的计算与试验应用研究参考。采用复杂介质体的二维电磁散射有限元数值计算方法，对介质体机翼剖面的缩比模型电磁散射规律进行了数值计算研究，发现若介质体阻抗比大于0.5，则缩比模型的雷达散射截面（RCS）试验结论不能按照导体修正原理还原，必须修正才能作为原构形介质体的电磁散射特性，这对于大型结构体小型化隐身技术测试具有实用价值与意义。

Numerical Study of Medium Stealth Scale-down Models for Airfoil Shape

Structured radar absorbing materials play an important role in the stealth technology of military air-vehicles for their omnidirectional effectiveness without the need to change the original aerodynamical shape configuration.But experimental study of stealth efficiency and parametric effects for full scale structures requires considerable financial support and testing space,which limits the application of experimental tests.Therefore,it is of significant value to find the electromagnetic dispersion laws of the scale-down medium and the modification method between scale-down and full scale vehicle configurations.This paper makes a numerical study of the electromagnetic dispersion law of a scale-down model for an airfoil-like complicated medium configuration by means of the 2-D electromagnetic finite element method.The numerical computation leads to the following conclusion: the radar cross section(RCS) test result of electromagnetic dispersion of a scale-down model cannot be directly converted into that of the real-world medium prototype under conductor modification principle if the medium impedance ratio is greater than 0.5,and necessary modification must be done.This conclusion is of practical significance for the stealth test of minifying large-scale medium configuration for military air-vehicles.