AN INVERSE OPTIMIZATION FOR MINIMIZING ENTRANSY DISSIPATION DURING HEAT TRANSFER PROCESSESZhihui Xie AbstractA class of finite-time heat transfer processes (HTPs) for entransy dissipation minimization is studied in this paper. Based on optimal control theory, the optimality condition is derived firstly, and then the general characteristics of heat transfer laws (HTLs) for three special temperature distributions including uniform temperature difference field, constant heat transfer rate per unit area, and constant entransy dissipation rate operations are obtained based on the optimality condition. The results show that the condition that the difference of temperature for the minimum entransy dissipation of heat transfer process (EDOHTP) is a constant is not only valid for Newtonian HTL [ q ∝ Δ(T) ], but also valid for generalized convective HTL [ q ∝ (ΔT)^{m} ] and complex HTL ( q ∝ [ (ΔT) + (ΔT)^{m} ] ); if the heat transfer rate per unit area is a constant when the EDOHTP achieves its minimum value, the difference of temperature between cold and hot fluids is also a constant; the entransy dissipation rate for the minimum EDOHTPes with generalized convective HTL is a constant. |
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