将非平衡态热力学理论应用于分析,导出了损率与推动力的一般关系,阐明了由不可逆过程引起损失的机理.结果表明,一种形式的推动力不仅引起该种形式的损失,而且由于不同形式的推动力之间的耦合而引起其它形式的损失;并进一步指出,工程中计算损失时,耦合项一般可以忽略.“,”By applying nonequilibrium thermodynamics theory to exergy analysis, the paper aims to derive the common relation between the rate of exergy destruction and the driving forces and expound the mechanism of exergy destruction caused by irreversible processes. The result shows that one type of driving force causes not only the same type of exergy destruction but also another type of exergy destruction resulting from the coupling between different types of driving force. The result also points out that for the calculation of exergy destruction in engineering, the coupling terms are generally negligible.