Abstract The entropy generation minimization and the entransy theory are widely used in the optimization of heat transfer. In this paper, the two theories are applied to coupled steady heat transfer systems. The two different definitions of radiative entransy flux are discussed. It is found that the extremum principle of entransy dissipation for coupled heat transfer systems can be obtained only when temperature is treated as the driving force of radiative heat transfer and the definition of entransy flux for radiative heat transfer is the same as that in conductive and convective heat transfer. Taking temperature as the driving force of radiative heat transfer, we have analyzed three coupled heat transfer examples, which are the one-dimensional coupled conductive and radiative heat transfer, the coupled convective and radiative heat transfer and the coupled conductive, convective and radiative heat transfer. The results show that the extremum principle of entransy dissipation always leads to the best system performance, while the entropy generation minimization does not always. The definition of radiative entransy flux in which the blackbody emissive power is treated as the driving force is also used for the three examples. However, the results show that neither the extremum radiative entransy dissipation rate nor the extremum conductive/convective entransy dissipation rate results in the best system performance. Therefore, this definition is not suitable for coupled heat transfer systems.

中文翻译：

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熵产生最小化和火积理论的耦合稳态传热过程分析

摘要 熵产生最小化和火积理论广泛应用于传热优化。本文将这两种理论应用于耦合稳态传热系统。讨论了辐射火积通量的两种不同定义。发现只有将温度作为辐射传热的驱动力，才能得到耦合传热系统的火积耗散的极值原理，并且辐射传热的火积通量的定义与传导和对流中的定义相同。传播热量。以温度作为辐射传热的驱动力，我们分析了三个耦合传热的例子，它们是一维耦合传导和辐射传热，对流与辐射耦合传热和传导、对流与辐射传热耦合。结果表明，火积耗散的极值原理总是导致最佳系统性能，而熵生成最小化并不总是如此。将黑体发射功率视为驱动力的辐射火积通量的定义也用于三个例子。然而，结果表明，无论是极值辐射火积耗散率还是极值传导/对流火积耗散率都不能导致最佳系统性能。因此，该定义不适用于耦合传热系统。结果表明，火积耗散的极值原理总是导致最好的系统性能，而熵生成最小化并不总是如此。将黑体发射功率视为驱动力的辐射火积通量的定义也用于三个例子。然而，结果表明，无论是极值辐射火积耗散率还是极值传导/对流火积耗散率都不能导致最佳系统性能。因此，该定义不适用于耦合传热系统。结果表明，火积耗散的极值原理总是导致最佳系统性能，而熵生成最小化并不总是如此。将黑体发射功率视为驱动力的辐射火积通量的定义也用于三个例子。然而，结果表明，无论是极值辐射火积耗散率还是极值传导/对流火积耗散率都不能导致最佳系统性能。因此，该定义不适用于耦合传热系统。结果表明，无论是极值辐射火积耗散率还是极值传导/对流火积耗散率都不能导致最佳系统性能。因此，该定义不适用于耦合传热系统。结果表明，无论是极值辐射火积耗散率还是极值传导/对流火积耗散率都不能导致最佳系统性能。因此，该定义不适用于耦合传热系统。