摘要
本文对平直翅片管翅式换热器在考虑翅片效率和不考虑翅片效率2种情况下分别进行了层流状态下的流动和换热的三维数值模拟,研究了2种情况下Re数对换热量、Nu数及协同角的影响,并从场协同角度进行了分析。结果表明,Re数取200～1 700范围内的6个不同值,在不考虑翅片效率时,换热量分别增大了3.44%、4.76%、7.48%、12.68%、16.04%和19.56%。随着Re数的增大,翅片效率对模拟结果的影响也会增大,即在高Re数下不可忽视翅片效率对结果的影响。本文还从翅片效率的根本定义出发,得出了不同Re数下的翅片效率,为计算翅片效率提供了一个新的思路。
In this paper,a three-dimensional numerical study was performed for analyzing the laminar fluid flow and heat transfer of tube-and-fin heat exchanger with flat fins.Under the conditions of considering and neglecting the fin efficiency,the simulation results were compared.In detail,the effects of Reynolds number on heat transfer rate,Nusselt number and intersection angle for two conditions were discussed,also the numerical results were analyzed from the viewpoint of field synergy principle.Furthermore,six different values of Reynolds number ranged from 200 to 1 700 were investigated.The results showed that when fin efficiency was not considered,the heat transfer rate increased by 3.44%,4.76%,7.48%,12.68%,16.04% and 19.56%,respectively.With the increase of Reynolds number,the effect of fin efficiency on simulation results would be greater,that meant the fin efficiency could not be neglected under high Reynolds number conditions.In addition,the fin efficiency was calculated under different Reynolds number values according to its basic definition,hence a new idea for fin efficiency calculation was proposed.
出处
《建筑科学》
北大核心
2011年第10期98-101,110,共5页
Building Science
基金
江苏省科技成果转化专项资金项目(BA2006012)
关键词
管翅式换热器
翅片效率
数值模拟
场协同理论
tube-and-fin heat exchanger
fin efficiency
numerical simulation
field synergy principle
