熵产是非平衡热力学中的核心物理量,传统上表示为广义力(驱动力)与广义流的乘积.这种表达存在两方面缺陷:一是广义力与广义流的拆分具有任意性;更重要的是,以其计算热波传递时熵产可以为负值,从而违反热力学第二定律.本文基于热质理论分析表明,传热过程的熵产实质上是由热质流体的热质能耗散引起的,所以熵产中的力不是驱动力而是阻力,并且具有力的量纲.由此提出的熵产修正表达式,不仅在计算热波传递过程中熵产恒为正值,与扩展不可逆热力学中的熵产表达式一致,而且不存在力和流拆分的任意性.
The entropy production is expressed as the product of the generalized force(driving force) and generalized flux,which plays a central role in classical non-equilibrium thermodynamics.This expression has shortcomings in two aspects:first,the decomposition into generalized fluxes and forces is arbitrary to some extent;more importantly,the entropy production is negative value calculated in heat wave propagation,which breaks the second law.In this paper,we carry out analyses based on the thermomass theory and show that the entropy production is induced by the dissipation of thermomass energy during heat condution.The generalized force of entropy production is not driving force but resistive force,having a unit of force in Newton's mechanics.The modified expression for entropy production not only guarantees its positiveness in propagation of heat waves consistent with the extended irreversible thermodynamics, but also avoids the arbitrariness of decomposition.