换热网络的热流均匀性因子

摘要

This paper presented the uniformity factor of heat flux,which can evaluate the heat transfer efficiency of heat exchanger networks. The uniformity factor was analyzed under two conditions. Simulation was conducted under the condition of constant total heat transfer areas in the same structure,the corresponding relationship between the uniformity factor of heat flux and the heat transfer rate was investigated,and compared with the uniformity factor of temperature difference. Simulation was optimized under the condition of changing structures of heat exchanger networks,the corresponding relationship between the uniformity factor of heat flux and the heat transfer rate was investigated. The factor was validated in two specific heat exchanger networks. The results showed that the heat transfer efficiency of heat exchanger networks increased when the uniformity factor of heat flux decreased. The uniformity factor of heat flux in heat exchanger networks established in this paper could reflect the heat transfer efficiency of heat exchanger networks,it could also be a new evaluation index for the heat transfer efficiency,and a new idea for the synthesis and optimization of heat exchanger networks.%提出并建立了能够评价换热网络换热效能的热流均匀性因子，在两个条件下对该因子进行验证和分析。首先，在相同结构上保持换热器单元总面积之和不变的条件下模拟计算，考察热流均匀性因子与总换热量之间的对应关系，并与温差均匀性因子进行比较；其次，在改变换热网络结构的条件下优化计算，考察各优化结构的热流均匀性因子与总换热量之间的对应关系。通过两个具体的换热网络实例验证该因子，结果表明：热流均匀性因子越小则对应的换热网络总体换热效能越好。由此说明本研究建立的换热网络的热流均匀性因子能够从总体上反应换热网络的换热效能，能够作为其换热效能的一种新的评价指标，并能为换热网络的综合及优化提供新的思路。