Thermo-Mechanical Coupling Transport Model and Group Speed in Three-Phase-Finite Lag Non-Fourier Media
Zhang Xiaomin,Zhang Peiyuan,Peng Xianghe
(Dept. of Engineering Mechanics, Chongqing Uni.,Chongqing,400044)

Abstract: The basic solution of thermo-mechanical coupling prorogation in three-phase finite lag non-Fourier media is obtained, and the propagation group speed and its bound are determined. The basic solution corresponding to positive logarithmic temperature rising rate indicates that the spacial distribution of temperature and displacement in the exponential function propagate at the specified speed dependent on the logarithmic temperature rising rate. In the summation o f basic solutions, a constant propagation speed does not arise, but two groups peeds do as numerical sets bounded within finity. One group speed degenerates to expanding wave speed without thermo-mechanical coupling, i.e., first sound speed. And the another degenerates to temperature wave speed, whose upper bound is 0.6065 of the temperature wave speed in CV media.
Keywords: non-fourier law, three-phase-infinite-lag, thermo-mechanical Coup ling, group speed.