A Study on Orecise Quantification of Ultrasonic Inspection

1.编制了超声波在介质中传播的数值模拟程序。利用该仿真系统，研究了超声波的特性.利用超声脉冲回波检测技术研究了缺陷的散射波形特征。根据折射角的不同，将散射波分为纵向和横向分量.开发了计算机图形学系统，利用超声波在表面的回波信号，绘制出缺陷的形状，并给出了相移与缺陷形状的关系.分析了弹性体中存在非线性边界缺陷的情况。对非线性边界的活动性进行了数值分析，揭示了其特征.作为一种分析弹性波传播的计算方法，对有限元-边界元混合法进行了改进。结果表明，该分析方法能有效地减少分析模型的自由度。

1. Computational program to simulate the propagation of ultrasonic wave was developed. Using this simulation system, the characters of ultrasonic waveofrm was investigated.2. Ultrasonic Pulse-Echo inspection was carried out to investigate the character of scattering waveform from flaws. Scattering wave was divided into longitudinal and transverse components based on the difference of refraction angle.3. Computer graphics system was developed to picturise the shape of flaws from the echo of ultrasonic wave obtained on the surface.The relationship between phase shift and shape of flaw was shown.5. Analysis was carried out in case that a flaw with non-linear boundary existed in a elastic body. The activity of non-linear boundary was analyzed numerically and its characters was shown.6. As a computational technique to analyze the propagation of elastic wave, hybrid method of finite element method and boundary element method was improved. It was shown that this analysis method was effective to reduce the freedom of analysis model.