基于热固耦合的管道激光超声检测有限元模拟

Finite Element Simulation of Laser Ultrasonic Detection in Pipeline Based on Thermal Solid Coupling

对管道裂纹检测中的激光超声检测技术应用于X80管道时的测试进行研究,运用基于热固耦合的有限元方法对激光照射管道产生超声的过程进行模拟,得到了脉冲激光源功率密度特性图以及管道表面温度场的分布图,对模拟结果进行分析并得出相关结论。通过研究脉冲激光所激发的超声波在管道中的传播特性,分别得出了超声波在管道表面有裂纹和无裂纹时的振动曲线,阐述了裂纹深度对超声表面波的影响。搭建非接触式试验平台对该模拟方法进行验证,试验表明该方法能有效模拟管道激光超声检测的过程。

In this paper, the laser ultrasonic detection technology in pipeline crack detection is applied to the test of X80 pipeline. The finite element method based on thermal-solid coupling is used to simulate the process of ultrasonic generation by laser irradiation on the pipeline. And from the distribution map of the surface temperature field of the pipeline, the simulation results are analyzed and relevant conclusions are drawn. By studying the propagation characteristics of ultrasonic waves excited by pulsed laser in the pipeline, the vibration curves of ultrasonic waves with and without cracks on the surface of the pipeline are obtained, and the effect of crack depth on ultrasonic surface waves is described. A non-contact experimental platform was established to verify the simulation method. Experiments show that the method can effectively simulate the process of laser ultrasonic detection of pipelines.