Osara Jude A, Bryant Michael D
Surface Technology and Tribology, Department of Mechanics of Solids, Surfaces and Systems, University of Twente, 7522 NB Enschede, The Netherlands.
Mechanical Engineering Department, University of Texas at Austin, Austin, TX 78712, USA.
Entropy (Basel). 2024 Mar 7;26(3):237. doi: 10.3390/e26030237.
Entropy generation, formulated by combining the first and second laws of thermodynamics with an appropriate thermodynamic potential, emerges as the difference between a phenomenological entropy function and a reversible entropy function. The phenomenological entropy function is evaluated over an irreversible path through thermodynamic state space via real-time measurements of thermodynamic states. The reversible entropy function is calculated along an ideal reversible path through the same state space. Entropy generation models for various classes of systems-thermal, externally loaded, internally reactive, open and closed-are developed via selection of suitable thermodynamic potentials. Here we simplify thermodynamic principles to specify convenient and consistently accurate system governing equations and characterization models. The formulations introduce a new and universal Phenomenological Entropy Generation (PEG) theorem. The systems and methods presented-and demonstrated on frictional wear, grease degradation, battery charging and discharging, metal fatigue and pump flow-can be used for design, analysis, and support of diagnostic monitoring and optimization.
通过将热力学第一定律和第二定律与适当的热力学势相结合而得出的熵产生，表现为现象学熵函数与可逆熵函数之间的差异。现象学熵函数是通过对热力学状态的实时测量，在穿过热力学状态空间的不可逆路径上进行评估的。可逆熵函数是沿着穿过相同状态空间的理想可逆路径计算得出的。通过选择合适的热力学势，开发了各类系统（热系统、外部加载系统、内部反应系统、开放系统和封闭系统）的熵产生模型。在这里，我们简化热力学原理，以确定方便且始终准确的系统控制方程和表征模型。这些公式引入了一个新的通用现象学熵产生（PEG）定理。所提出并在摩擦磨损、润滑脂降解、电池充电和放电、金属疲劳及泵流方面得到验证的系统和方法，可用于设计、分析以及支持诊断监测和优化。
