基于场协同原理的横排锯齿翅片湍流传热强化机理

Heat transfer enhancement mechanism of transverse direction type serrated fin in turbulent flow based on field synergy principle

通过数值模拟方法分析了横排(TD)锯齿翅片在板翅换热器通道内传热与流动特性.研究了湍流条件下横排锯齿翅片的温度场,速度场以及两场协同性,探索其强化传热机理.在此基础上获得了翅片高度,翅片间距和翅片宽度对传热与流动的影响规律,并给出了横排锯齿翅片的综合传热性能因子.结果表明:横排锯齿翅片通道内流体扰动强烈,形成了周期性纵向涡流;改善了通道内速度与温度梯度场之间的协同作用,强化传热效果,提高了综合传热性能因子.

The heat transfer and flow characteristics of TD （transverse direction） type serrated fin in plate-fin heat exchanger were studied numerically. To explore the heat trans- fer enhancement mechanism of TD type serrated fin, three dimensional numerical model was established to examine the temperature gradient field, velocity field and fields synergy in tur- bulence flow. Furthermore the effect of fin height, fin space and fin width on the heat trans- fer and flow characteristics were analyzed respectively. The integrated heat transfer perform- ance factor were calculated. Results show that： the temperature field and velocity distribu- tion was uniform; periodic longitudinal vortex was formed because of the fin strong disturb- ance; the synergy of velocity field and temperature gradient was improved owing to vortex enhancing the heat transfer efficiency and improving integrated heat transfer performance factor.