矩形法兰孔孔口模态辐射阻抗的计算与分析*

针对半空间矩形法兰孔孔口模态辐射阻抗计算困难的问题,提出一种模态辐射阻抗的计算方法。该方法通过坐标变换将四重积分转换为二重积分并消除奇异积分,且将这一系列过程通过MATLAB内置函数直接实现,显著降低了模态辐射阻抗计算的复杂程度。通过对比与分析,验证了该方法的正确性,得到了自模态辐射阻抗随模态阶次增加峰值逐渐往高频移动且呈减小趋势、互模态辐射阻抗相比于自模态辐射阻抗小到可以忽略不计的性质。

Modal radiation impedance calculation and analysis of flanged rectangular aperture orifice

Aiming at the difficulty in calculating modal radiation impedance of flanged rectangular aperture orifice, a method for modal radiation impedance calculation was presented. In this method, the quadruple integral was transformed to double integrals and the singular integrals were eliminated via coordinate transformations. All the procedures were implemented in MATLAB by its built-in functions directly and the complexity of modal radiation impedance calculation was decreased dramatically. The method was validated and properties of modal radiation impedance were obtained via calculation and analysis. The analysis shows that: the amplitude frequency of modal radiation impedance is increased and the amplitude is decreased with the increasing of modal order, the amplitude of cross-modal radiation impedance is negligibly small compared to self-modal radiation impedance.