全玻璃真空太阳能热水器内流场的影响因素分析  

ANALYSIS ON FACTORS INFLUENCING FLUID FLOW IN AN ALL-GLASS VACUUM TUBE SOLAR WATER HEATERS

作　　者：闫素英[1] 田瑞[1] 于文艳[1] 李嵩[2] 

机构地区：[1]内蒙古工业大学能源与动力工程学院,内蒙古呼和浩特010051 [2]清华大学工程力学系,北京100084

出　　处：《工程热物理学报》2010年第4期641-643,共3页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.50766002);内蒙古自然科学基金资助项目(No.20080404MS0701)

摘　　要：本文通过对均匀加热条件下的全玻璃真空管太阳能热水器内流场的计算流体力学模拟,研究了管内的对流换热过程,分析了器内流场的影响因素以及真空管与水箱连接处的流体速度、温度分布,计算与实验结果相一致,结果表明,在真空管与水箱连接处出现随机的涡流,对换热过程不利,特别是对于增加反射板的类似真空管双面受热的热水器情况,应采取措施确保管内对流换热流动的有序性。The aim of the paper is to investigate fluid flow in the solar water heater by means of the computational fluid dynamics（CFD）.The investigation was carried out with a focus on the convective heat transfer in the tube and influence factors.The buoyancy induced flow circulation and temperature in different parts of the tube was analyzed.The numerical simulation result is consistent with the result acquired by the experiment method.It is shown that fluid flow in the connection of the tube and water tank becomes stochastic and turbulent The flow instability leads to mixing of the warm uprising flow and the cold downward flow,which decreases efficiency of the heat exchange process.It is necessary to take effective steps to prevent the flow instability and secure the flow circulation in the tube.

关 键 词：全玻璃真空管太阳能热水器 速度场 温度场 CFD 

分 类 号：TK515[动力工程及工程热物理—热能工程]