热波传递过程中的熵产分析

Entropy Analysis in the Heat Wave Propagation

傅里叶导热定律导出的温度演化方程将得出无限大的热扰动传播速率。为了克服这个问题,一些修正导热模型被提出,可以得到双曲型温度方程,保证有限的热波传播速率。但是,新的传热模型得出的温度演化将使现有的不可逆热力学中熵产不能保持正定。拓展不可逆热力学通过修正熵以及熵产的表达式,使双曲导热也能得到正定的熵产率。热质理论用力学的概念分析热波传递过程中的热质能耗散与熵产的关系,对熵产的来源做了新的解释。热质理论得出的熵产表达式在双曲导热过程中保持正定,并指出,波动传递过程中的干涉是导致熵产率非均匀变化的原因。

An infinite propagation velocity is predicted by the evolution function of temperature induced by the Fourier＇s heat conduction law. Several modified model have been presented to overcome this problem. However, the entropy production of hyperbolic models cannot keep positive. The extended irreversible thermodynamics modifies the expression of entropy and its production rate to get them positive definite in hyperbolic models, the relation between the dissipation of thermomass energy and entropy production is analysed through a mechanical concept based on the thermomass theory. The wave interference is the cause of nonuniform change of entropy production rate.