带状渐变非均匀介质中波的传播

Wave Transmission in a Continuous Transitional Inhomogeneous Zone

对弹性波在带状渐变非均匀介质中的传播进行了研究 .建立了非均匀介质中波动方程的一般形式 ;利用走时变换 ,考虑边界条件、辐射条件和非均匀带两端的连续条件对变系数偏微分方程式进行求解。对 3种不同的具有二次变化的带状非均匀介质中波的传播得出了解析解 ,并进行了实例计算 .在非均匀介质区域中的弹性模量不同变化情况下 ,得到了不同区域长度与接收波波幅之间的变化规律曲线 ,讨论了弹性波在非均匀介质中传播的一般性质 .这些均为无损检测或波动反分析提供依据 .

The elastic wave transmission of two different homogeneous materials in a continuous transitional inhomogeneous zone was studied. The general equations of the elastic wave transmission in inhomogeneous zone were established. Based on delay-time transformation, the differential equation with varied coefficient was solved by taking into consideration the boundary, radiation and continuum conditions. The closed solutions were gained and the calculation values were applied in three examples to show that the wave was transmitted in a continuous transitional inhomogeneous zone with varying quadratic forms. For wave transmission in inhomogeneous media with different distributions of elastic modulus, the curves of the relationship between the amplitude of the received wave and the length of the zone were obtained. And the general properties of elastic wave transmission were discussed. This can provide basis for nondestructive tests or the inversion analysis of wave motions.