孔隙介质包裹的充液管道结构中导波传播特性

研究孔隙介质包裹的充液管道中纵向导波传播特性,分析孔隙介质参数对频散曲线的影响。建立了孔隙介质包裹充液管道的结构模型,利用孔隙介质弹性波动理论,建立对应的频散方程,数值模拟计算得到该模型的频散曲线和时域波形,并分析了孔隙介质参数以及管壁厚度对频散曲线的影响。结果表明孔隙介质的渗透率对于导波频散的影响较小,孔隙度的改变对时域波形的位移幅度影响较大。同时,导波存在衰减,且衰减随孔隙度增大而增大。所得结论为埋地管道无损检测方面提供一定理论参考。 

Propagation characteristics of guided waves in a liquid filled pipe embedded in a porous medium

To research on wave propagation characteristics of a liquid filled pipe embedded in a porous medium, and analyze the effect of the parameters of porous media on the dispersion, a model of a liquid filled pipe embedded in a porous medium is built. Based on the elastic-dynamic theory of liquid-saturated porous solid, the corresponding dispersion equations are established. Through numerical simulation, the characteristic of dispersion and time domain waveform with different thickness of pipe and porous medium parameters are discussed. Results show that the porosity has little impact on dispersion, and the attenuation of guided wave increases with porosity, whilst the porosity influences the displacement amplitude of the time domain waveform. It is hard to show the difference of dispersion when the permeability of the media changes. The drawn conclusion can provide some theoretical instruction and guidance for buried pipe nondestructive testing.