声表面波在空心圆柱体中的传播特性分析

Analysis of propagation characteristics of surface acoustic wave in hollow cylinder

空心圆柱体管道类的声表面波检测是目前工程检测领域常见的问题。通过势函数和位移假设,建立了声表面波在空心圆柱体内传播的频散方程。数值计算结果表明在空心圆柱体内传播的声表面波与平板中传播的兰姆波存在类似,位移表现为对称和反对称模态。随着频率的增加,低阶模态的相速度逐渐趋于声表面波波速,同时空心圆柱体的壁厚对声表面波相速度的影响较为明显。建立的模型和计算结果为实际的声表面波圆柱体检测奠定了基础。

Surface acoustic wave detection of hollow cylinder pipe is a common problem in the field of engineering detection.Based on the assumption of potential functions and displacements,the dispersion equation of surface acoustic wave propagating in a hollow cylinder is established.The numerical results show that the surface acoustic wave propagating in a hollow cylinder is similar to the Lamb wave propagating in a flat plate,and the displacements are symmetric and antisymmetric.With the increase of frequency,the phase velocity of the lower modes tends to the surface acoustic wave velocity,and the wall thickness of the hollow cylinder has a significant effect on the surface acoustic wave phase velocity.The established model and calculation results lay a foundation for the actual surface acoustic wave cylinder detection.