考虑到流体的可压缩性,笔者进一步发展了以前的结果。引进了准微观连续条件的概念,直接联合应用流体动力学方程和固体的弹性或粘弹性力学方程,即得到了此种介质的动力学方程组,其中直接引用了流体和固体的弹性(或粘弹性)系数,较之Biot从物理考虑而建立的应力—应变关系中的后两个常数Q、R具有更明确的物理意义,因而更便于用常规的方法确定。证明了,此种无限介质中通常具有两种P波和一种S波,且具阻尼和频散效应。对于几种极端情况可以明确地得到固体波和流体波,有助于近似地解释一些地球物理和声学现象。文中还指出了区分两种典型的计算模型的重要意义。 Taking into account the fluid compressibility, the author further developed the previous results. The concept of quasi-microscopic continuous conditions was introduced to directly apply the hydrodynamic equations and the elastic or viscoelastic mechanical equations of solids to obtain the kinetic equations of such media, which directly quoted the fluid and solid elasticity Elastic) coefficients, which have a more definite physical meaning than the latter two constants Q and R in the stress-strain relationship established by Biot from physical considerations, and thus are easier to determine by conventional methods. It is proved that this kind of infinite medium usually has two kinds of P wave and one kind of S wave with damping and dispersion effect. Solid and fluid waves can be clearly obtained for several extremes, helping to approximate some of the geophysical and acoustic phenomena. The paper also points out the importance of distinguishing two typical computing models.