换热器传热过程的分析

Exergy Analysis of Heat-Exchange Process of Heat-Exchanger

本文以热力学第二定律为理论依据，对换热器的 损失．效率进行了分析。导出了同时考虑热 损失和流阻 损失时的损失、 效率的计算公式，结果表明，考虑了流阻 损失后，换热器的 损失、 效率可能出现极值点。当热负荷一定时，换热器的管径，冷热流体的流速应合理匹配使换热器的 尽可能地得到利用。

Through the exergy analysis of heat-exchange process,the author in this paper has derived the calculation formilae of exergy low(ΔE) & exergy efficieency(η'E)under the circumstances of cosidering heat exegy low and flow exergy low simultaneoraly. the results show that there is a possible esistence of the limit point of ΔE & η'E. when load of heat-exchanger (Q)is constant. To make use of exergy of heat-exchanger as much as .possible,the diameter of h6at-exchanger and the flow rate of cold & heat fluid should be appropriately matched.