内可逆四热源吸收式热变换器生态学最优性能

Ecological optimal performance of endoreversible four-heat-reservoir absorption heat-transformer

基于能量分析的观点 ,建立了反映四热源吸收式热变换器泵热率与熵产率之间最佳折衷的生态学准则 ,导出了线性 (牛顿 )传热定律下生态学目标与泵热系数的优化关系、最大生态学目标值及其相对应的泵热系数、泵热率和熵产率以及最大泵热率时的生态学目标和熵产率。通过数值算例分析得到了吸收式热变换器的生态学优化准则。计算发现 ,与最大泵热率目标相比 ,最大生态学目标牺牲了 2 7.3%的泵热率 ,使循环熵产率降低了 77.0 % ,泵热系数增加了 55.4 % 。

On the basis of an endoreversible four heat reservoir absorption heat exchanger cycle with linear (Newtonian) heat transfer law, an ecological optimization criterion was proposed for the best mode of operation of the cycle, which consisted of maximizing a function representing the best compromise between the heating load and the entropy production rate. The optimal relation between the ecological criterion and the coefficient of performance, the maximum ecological criterion and the corresponding coefficient of performance, heating load and entropy production rate, as well as the ecological criterion and entropy production rate at the maximum heating load were derived using finite time thermodynamics. Numerical results show that compared with the maximum heating load criterion, the maximum ecological criterion yields an 77.0% decreases in entropy production rate and 55.4% increases in coefficient of performance at the cost of 27.3% of heating load. This indicates that ecological criterion is an optional objective for the optimal design of absorption heat transformers with long term benefits.