Behaviors of thermophysics properties of supercritical fluid, diverging or vanishing on its gas-liquid critical point, result in the unique heat and mass transfer process: thermal-mechanical effect. With the asymptotic analysis of hydrodynamics equations for supercritical fluids based on the order difference among the thermal parameters of near-critical fluid, a dominant physical process can be found to analyze the character of the thermal wave process under various conditions. In this paper, analyses and calculations of the asymptotic model with different thermophysics properties model are conducted. The calculation results from different thermophysics properties models and boundary conditions are also discussed to study the detailed mechanism of heat and mass transfer of near-critical fluid.