The influence of viscous heating on the entransy in two-fluid heat exchangers

作     者：GUO JiangFeng XU MingTian CHENG Lin 

作者机构：Institute of Thermal Science and Technology Shandong University Jinan 250061 China Insititute of Engineering Thermophysics Chinese Academy of Science Beijing 100190 China 

出 版 物：《Science China(Technological Sciences)》 (中国科学（技术科学英文版）)

年 卷 期：2011年第54卷第5期

页      面：1267-1274页

核心收录：

学科分类：080706[工学-化工过程机械] 080701[工学-工程热物理] 08[工学] 0807[工学-动力工程及工程热物理] 

基　　金：supported by the National Basic Research Program of China ("973" Program) (Grant No. 2007CB206900) 

主　　题：entransy entransy dissipation viscous heating heat exchanger entropy generation 

摘      要：In the present work, water and olive oil are taken as working fluids to study the influence of viscous heating on the entransy dissipation caused by heat transfer in two-fluid heat exchangers. The results show that the influence of viscous heating on the entransy loss associated with heat transfer can not be neglected for the liquids having large dynamic viscosity. The viscous heating effect maintains the heat transfer ability of the working fluids, relatively reduces the entransy loss in heat exchangers; the viscous heating effect relatively augments the entropy generation due to heat transfer and the available energy destruction in heat exchangers. For the working fluid having large dynamic viscosity, the increasing rates of the entransy and entropy generation contributed by the viscous heating are even larger than those contributed by heat transfer, when the mass flow rate of working fluid reaches a certain value under the fixed heat transfer area condition. Thus, the entransy loss rate decreases and the growth rate of entropy generation increases as the mass flow rate of the working fluid increases. Under the same other conditions, the heat transfer entransy loss rate and entropy generation rate per unit heat transfer rate obtained when the fluid having a smaller heat capacity rate is cold fluid are less than those obtained when the fluid having a smaller heat capacity rate is hot fluid.