流体参数与隔板结构对太阳能蓄热水箱性能的综合影响

Comprehensive effect of fluid parameters and obstacle structure on performance of solar energy storage tank

为了探寻综合性能最优的蓄热水箱结构,以半球形顶圆柱体水箱为研究对象,通过改变内置水平隔板上开孔的面积、数量及位置,得到13种不同的隔板结构,数值分析了不同冷水入口流速对水箱内温度场和流场的影响特征。结果表明:水箱内置隔板上的不同开孔方式对冷热水混合过程的抑制效果存在差异,本文开孔方式2对用户侧用水量变化的适应性较强。隔板开孔面积不变,增大冷水入口流速或增加开孔数量均能有效提高水箱蓄热量;冷水入口流速不变,在较小的总开孔面积条件下减小各小孔定位圆直径可有效提高水箱蓄热量,6#水箱蓄热量最大。过高、过低的冷水入口流速均不利于形成良好的温度分层,11#水箱的温度分层效果最佳。

In order to find the optimal structure of solar energy storage tank,the cylinder water tank with hemispherical top is taken as the research object.By changing the area,number and location of the holes on the built-in horizontal obstacles,13 obstacles with different structure are obtained.The influences of inlet velocity of cold water on the temperature field and flow field of the tanks are numerically analyzed.The results show that the inhibition effect of different opening mode on obstacles on the mixing process of hot and cold water is different.In this study,the opening method 2 has a strong adaptability to the change of the user water consumption.The heat storage capacity of the tanks can be effectively increased by increasing the inlet velocity of cold water or increasing the number of holes on obstacles when the opening area is unchanged.And keep the inlet velocity of cold water unchanged,the heat storage capacity of the tanks can be effectively increased by reducing the diameter of the locating circle of holes on obstacles under smaller opening area.Tank 6 has the maximum heat storage capacity.Too high or too low inlet velocity of cold water is not conducive to the formation of good temperature stratification in tanks.And the tank 11 has the highest temperature stratification efficiency for all the studied modes.