A finite-time thermodynamic (FTT) model of three-heat-reservoir thermal Brownian refrigerator is established in this paper. This model can be equivalent to the coupling of a thermal Brownian engine and a thermal Brownian refrigerator with heat transfer effects. Expressions for cooling load and coefficient of performance (COP) are derived by combining FTT and non-equilibrium thermodynamics (NET). The system performance is studied and compared with those of previous models. For fixed internal parameters, the thermal conductance distributions among three heat exchangers are optimized for maximal cooling load. For fixed inventory allocations, the internal parameters are also optimized for maximal cooling load. Finally, the double-maximum cooling load is obtained by optimizing internal parameters and external thermal conductance distributions simultaneously, and the optimal operating temperatures are also derived. Results show that half of total thermal conductance should be placed in condenser to reject heat to ambient under maximal cooling load regime. The heat transfer determines system performance by controlling the working temperatures and the coupling of two external loads. The system works in reversible state when COP reaches its maximum value. The new performance limits can predict that of three-heat-reservoir thermal Brownian refrigerator more accurately, and also include those of NET model.

中文翻译：

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传热效应对三热库热布朗制冷机性能的影响

建立了三热库热布朗制冷机的有限时间热力学（FTT）模型。该模型可以等效为具有传热效应的热布朗发动机和热布朗制冷机的耦合。冷负荷和性能系数 (COP) 的表达式是通过结合 FTT 和非平衡热力学 (NET) 得出的。研究了系统性能并与以前的模型进行了比较。对于固定的内部参数，三个热交换器之间的热导分布针对最大冷却负载进行了优化。对于固定库存分配，内部参数也针对最大冷却负载进行了优化。最后，通过同时优化内部参数和外部热导分布，获得双最大冷负荷，并推导出最佳运行温度。结果表明，总热导的一半应放置在冷凝器中，以在最大冷却负载状态下将热量排出到环境中。传热通过控制工作温度和两个外部负载的耦合来决定系统性能。当COP达到最大值时，系统工作在可逆状态。新的性能极限可以更准确地预测三热库热布朗制冷机的性能极限，并且还包括NET模型的性能极限。