加装导流板的全玻璃真空管太阳能热水器数值模拟分析

Numerical Simulation Analysis of All-Glass Vacuum Tube Solar Water Heater with Baffle

针对目前全玻璃真空管热水器冷、热水共用一个流道,在管内及入口处会产生冷热水混合现象,多处出现随机涡流,导致集热效率低下的问题,集热过程由对流、热传导和热辐射3种方式同时进行,系统内部的换热性能与当地气候状况及使用环境有关,还与热水器的内部结构有关。本文建立了真空管内加装导流板结构模型,运用了Ansys Fluent软件对加装导流板结构的热水器进行三维数值模拟研究,分析了导流板结构对集热系统传热的影响。结果显示:在真空管中心沿轴向位置加装导流板后,管内多处涡流几乎不存在,使流体流动变得相对稳定,相比无导流板结构更有利于管内流体自然对流循环,同时能量损失降低,换热效果增强。

The heat collection process of all-glass vacuum tube solar water heater is carried out simultaneously by convection,heat conduction and heat radiation.The internal thermal performance of the system is not only related to the local climate,but also related to the internal structure of the water heater.In this paper,through consulting related literature,it is proposed to install a guide plate in all-glass vacuum tube solar water heater.Through numerical simulation and analysis,the internal structure of the water heater can be optimized,and the flow and heat exchange of cold and hot fluids in the water heater can be improved.