扭带强化传热性能的数值与实验研究  

Numerical and experimental studies on heat transfer enhancement of twisted tape inserts

作　　者：满长忠[1] 郁双鑫 胡敬伟 孙培岩[1] MAN Chang-zhong;YU Shuang-xin;HU Jing-wei;SUN Pei-yan(School of Energy and Power Engineering, Dalian University of Technology, Dalian 116024 , China)

机构地区：[1]大连理工大学能源与动力学院,辽宁大连116024

出　　处：《热科学与技术》2019年第2期121-129,共9页Journal of Thermal Science and Technology

摘　　要：通过模拟和实验的方法研究在湍流工况下(3 000<Re<10 000)换热器管内插入不同扭带模型后的传热特性和阻力特性。区别于传统螺旋扭带,提出一种顺时针与逆时针交替扭转的正反扭带。对不同扭率的传统扭带以及扭率为3的无缺口和半圆缺口正反转扭带进行模拟计算,并将模拟结果与实验结果进行对比验证。结果表明:在湍流流态下,雷诺数越小,扭带的强化换热效果表现越好;对不同扭率的扭带,其努塞尔数、摩擦系数和综合性能指标随扭率的减小而增大;扭率为3时,两种正反扭带的强化换热效果均优于传统扭带,无缺口正反扭带的换热效果最好;模拟计算的结果数据与实验结果数据比较,最大误差不超过8%。The heat transfer and resistance characteristics of a heat exchanger with different twisted tape inserts under turbulent conditions (3000<Re<10000) were numerically and experimentally studied. Different from typical twisted tape (TT), the Left-Right twisted tape (LRTT) which alternates clockwise and counterclockwise was proposed. The characteristics of TTs with different twisted ratios, the non-cut and semicircle-cut LRTT with the twisted ratio of 3 were numerically studied. The comparisons in data of simulations and experiments were carried out. The results showed that the heat transfer enhancement effect of twisted tapes increases when the Reynolds number decreases in turbulent flow. For the typical twisted tapes with different twisted ratios, the Nusselt numbers, friction factors and performance evaluation criteria (PEC) increase with the decrease of twist ratios. When the twisted ratio is 3 , the heat transfer enhancement performances for two types of LRTT are better than that for TT, and the performance of the non-cut LRTT is best. The maximum error for data of simulations and experiments were less than 8%.

关 键 词：数值模拟 强化传热 正反转扭带 湍流 

分 类 号：TK172[动力工程及工程热物理—热能工程]