【摘要】 对压缩式热泵系统火用效率的定义式进行了分析 ,指出了该定义式在实际应用过程中存在的一些不足。即当低温热源为环境时 ,此定义式合理 ,否则即使热泵系统内部可逆 ,系统火用效率仍不为 1,文中对产生这一问题的原因进行了分析。以热泵系统的火用平衡方程为依据 ,参照火用效率定义方法及火用效率的基本特征 ,对压缩式热泵的系统火用效率进行了重新定义。通过对两个不违背火用效率定义特征的表达式的对比分析 ,确定了热泵系统合理的火用效率表达式。最后说明 ,在压缩式制冷系统中当高温热源不为环境时 ,火用效率定义也存在同样缺陷 ,改进方法与本文类似。更多还原

【Abstract】 After an analysis of the method for defining the exergy efficiency of a compression-type heat pump some deficiencies of such a definition during its practical use are pointed out. This means that in an environment of low-temperature heat source the definition under discussion has been found to be rational. Otherwise, even with an endo-reversible heat pump system the exergy efficiency of the system will still not be "unity". The cause which gives rise to such a problem is analyzed. By adopting the exergy balance equation or the heat pump system as a basis and referring to the basic characteristics of exergy efficiency and its definition method the exergy efficiency of a compression-type heat pump is defined once again. Through a contrast analysis of two expressions not contradictory to the exergy-efficiency definition characteristics determined is a rational expression of the exergy efficiency for the heat pump system. In conclusion, it is noted that in the absence of an environment of high-temperature heat source for a compression-type refrigeration system the same defect may emerge with regard to the definition of the exergy efficiency. In such a case a similar method for coping with the defect can be put into use.更多还原