中文摘要：

为了更好地反映超声波检测过程中各种缺陷产生的复杂散射波场特性,从无限固体介质的线弹性本构关系出发,用势函数表示波动方程,引入势函数和位移的关系,推导出适用于各种波形的人工截断边界应力的计算公式。采用应力边界条件对固体中超声波的传播进行数值模拟时,介质边界单元体表面的应力大小与分布需满足介质的本构关系和穿过人工边界向外辐射的波动方程,边界节点与内部节点的反应采用相同的积分格式计算。数值算例和实验结果表明,采用应力边界条件的数值模拟结果误差很小,能够很好地反映超声波检测过程中各类缺陷产生的复杂散射波场特性。

英文摘要：

In order to reflect the complex scattered wave field characteristics generated by irregular defects in the process of ultrasonic inspection,a formula for calculation of stress in artificial boundary was given herein.The formula could be applied to all waveforms.When artificial stress boundary was applied in numerical simulation for ultrasonic wave in solid,the size and distribution of stress in media boundary element＇s surface required to meet the constitutive relation of media and wave equation radiated through the artificial boundaries,the response of boundary nodes and finite element nodes were calculated by the same integral method.Numerical examples demonstrate that the deviation of the proposed boundary is very small,can reflect the the complex scattered wave field characteristics generated by various types of defects in the process of ultrasonic inspection.