Abstract The objectives of this research are to apply entropy production theory into cavitating flows and investigate dynamic characteristics of entropy production rate (EPR). A thermodynamic cavitation model and a density corrected turbulence model was adopted to this simulation around NACA0015 hydrofoil. Entropy production as a new method for evaluating energy performance is applied on thermodynamic cavitating flows. Cavitation effects on entropy production are firstly derived and revealed. Different entropy production terms by direct dissipation (EPDD), turbulent dissipation (EPTD), wall shear stress (EPWS), mean and fluctuating temperature gradients (EPMT and EPFT) were established in unsteady cavitating flow at 343 K to understand the interactions between cavitation and entropy. The results indicates that entropy production has strong association with cavitation. And entropy production rate by cavitation (EPRC) was derived firstly to evaluate the effects of phase change on entropy production rate. The entropy production rate by cavitation mainly focuses on the interface of cavity where there has intensive mass transfer procedure. Total entropy production rate (TEPR) mainly focuses on leading edge of hydrofoil, rear of attached cavity, detached cavity. Direct and turbulent entropy production rate are two main part in thermal cavitating flows. Direct entropy production can better reflect how total entropy production is distributed. Velocity gradients and phase change are two dominate factors controlling entropy change. In one cycle, total entropy production firstly decreases to its minimum and keeps stable to the inception stage of detached cavity collapse, then increases and fluctuates with cavity collapse.

中文翻译：

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考虑局部可压缩性的热力学空化流熵产分析

摘要 本研究的目的是将熵产生理论应用到空化流中，研究熵产生率（EPR）的动态特性。该模拟采用热力学空化模型和密度校正湍流模型围绕 NACA0015 水翼进行。熵产生作为一种评估能量性能的新方法被应用于热力学空化流。首先推导出和揭示空化对熵产生的影响。通过直接耗散 (EPDD)、湍流耗散 (EPTD)、壁面剪切应力 (EPWS)、平均和波动温度梯度（EPMT 和 EPFT）在 343 K 的非定常空化流中建立了不同的熵产生项，以了解空化和熵。结果表明熵产生与空化有很强的关联。并首先推导了空化熵产生率（EPRC），以评估相变对熵产生率的影响。空化产生的熵主要集中在传质过程密集的空腔界面。总熵产率（TEPR）主要集中在水翼的前缘、附着腔的后部、分离腔。直接和湍流熵产生率是热空化流动的两个主要部分。直接熵产可以更好地反映总熵产的分布情况。速度梯度和相变是控制熵变的两个主要因素。在一个循环中，