热漏和有限热源对两源制冷机最优构型的影响

The Effect of Heat Leak and Finite Low-Temperature Reservoir on the Optimal Configuration of a Two-Heat-Source Refrigeration Cycle

考虑一类存在热漏和低温热源有限的两热源制冷机，寻求其在给定循环周期和吸热量（也即给定制冷率）下制冷系数最大的最优构型。所述模型包括了４种特殊情形：（１）无热漏且无限热容低温热源；（２）无热漏但低温热源有限；（３）有热漏但低温热源无限；（４）有热漏且低温热源有限。分析中设传热服从牛顿定律。结果表明，对无限热容热源情形，热漏的存在不改变循环最优构型；对无热漏情形，有限热容热源使循环构型成为某种“广义卡诺制冷循环”；同时存在热漏且有限热源时，循环的构型与前几种完全不同。

The optimal configuration of a two-heat-source refrigeration cycle in which themaximum coefficient of performance can be obtained under a given cycle time and absorbedheat(that is a given rate of refrigeration)is determined with the considerations of heat leakand finite heat capacity low-temperature reservoir. The four special models are as follows :(1) infinite low-temperature reservoir without heat leak,(2) finite low-temperature reservoirwithout heat leak,(3)infinite low-temperature reservoir with heat leak , and(4)finite low-temperature reservoir with heat leak.It is assumed that the heat transfer obeys Newton'slaw. It is shown that the exsistance of heat leak doesn't change the configuration of the cyclewith infinite iow-temperature reservoir , the finite heat capacity of low-temperature reservoirwithout heat leak makes the cycle become a generalized Carnot refrigeration cycle and thereexists a great difference of the cycle configuration for the finite low-temperature reservoirwith heat leak and the former three cases.