周期性固—气粗糙界面的超声波衍射

建立了基于模式匹配法的周期性固－气界面声波衍射理论模型，其求解稳定，精确，优于直接边界积分法，采用该模型进行银－气锯齿界面的超声频谱预测，结果表明，周期性粗糙界面导致在某些频率处的反射叔谱奇异极小值为波型转换的结果。

Diffraction of Ultrasonic Waves from Periodically Solid-Gas Rough Surfaces

The diffraction of acoustic wave on periodic solid gas surfaces was modeled based on the mode matching equation approach,and the stability and accuracy of the solution are high and superior to the conventional boundary integral equation approach.The model is used to predict the spectrum of diffraction coefficients of periodic silver gas saw tooth surfaces.The results show that in the spectrum of the reflection coefficient frequency minima result from the mode conversion when the wave impinges on the rough surfaces.Therefore, the prediction of ultrasonic minima will help for improving the accuracy of ultrasonic quantitative testing.