环置曲面三角形涡产生器翅片管束通道内流动与传热特性数值研究  

Numerical study on flow and heat transfer characteristics of finned tube bundle with curved delta-winglet vortex generators

作　　者：张玲 林志敏 李圣帆 石文奎 王良璧 ZHANG Ling;LIN Zhimin;LI Shengfan;SHI Wenkui;WANG Liangbi(Key Laboratory of Railway Vehicle Thermal Engineering of MOE,School of Mechanical Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学机电工程学院铁道车辆热工教育部重点实验室,甘肃兰州730070

出　　处：《热科学与技术》2024年第4期403-412,共10页Journal of Thermal Science and Technology

基　　金：国家自然科学基金资助项目(51676093);兰州交通大学百名青年优秀人才培养计划资助项目

摘　　要：平直翅片管翅式换热器翅片侧通道内的马蹄形涡的强度有限,而在翅片表面冲压三角形曲面涡产生器可以诱导产生强烈的二次流,从而增强翅片表面的传热性能。采用数值方法对环置曲面涡产生器翅片管束通道内的流动与传热进行了模拟,并采用无量纲参数Se量化了翅片管束通道内的二次流强度。对比分析了平直翅片管束通道和环置曲面三角形涡产生器翅片管束通道内二次流特性及翅片表面传热特性,进一步分析了圆管前端的曲面涡产生器的周向位置及径向位置对其二次流特性和传热性能的影响,并探讨了翅片侧通道内二次流特性和传热特性的关系。结果表明:环置曲面三角形涡产生器可在通道中产生较强的二次流,同时涡产生器的引流作用明显改善了管后尾涡区的传热性能,从而提高了换热器整体换热性能。在较高Re条件下,环置曲面涡产生器起到强化传热作用。在所研究的参数范围内,最优结构参数与Re有关,当DVG1/D_(c)=1.55,β_(1)=105°和Re=2 500时,强化传热因子J_(F)可达1.23。The intensity of the horseshoe vortex in the fin side channel of the plain fin tube heat exchanger is limited, while the curved delta-winglet vortex generators punched on fin surface can generate stronger secondary flow to improve the heat transfer performance of fin surfaces. The fluid flow and heat transfer performance in the fin side channel of annular curved vortex generator is simulated numerically, and the intensity of the secondary flow in the fin side passage is quantified by using the dimensionless parameter named for Se. The secondary flow and heat transfer characteristics of the channel formed by circular tube bank plain fins with or without curved delta-winglet vortex generator are compared, the effects of the circumferential and radial position of the curved delta-winglet vortex generator on the secondary flow and heat transfer performance are also analyzed, and the relationship between secondary flow characteristics and heat transfer characteristics in fin side channels is discussed as well. The results show that the stronger intensity of secondary flow in the channel can be generated by curved delta-winglet vortex generators placed around the tube, and the vortex generator improves the heat transfer performance in the wake region behind the tube as well as the overall heat transfer performance of the heat exchanger. Under the higher Reynolds numbers, the vortex generator can greatly enhance the heat transfer performance of heat exchanger. In the range of parameters studied, the optimum geometry parameter is associated with Re, when D_(VG1)/D_(c)=1.55, β_(1)=105° and Re=2 500, the thermal performance factor J_(F) is up to 1.23.

关 键 词：翅片管束通道 强化换热 二次流 曲面涡产生器 数值模拟 

分 类 号：TK01[动力工程及工程热物理]