太阳能烟囱发电装置的CFD模拟

A numerical study on solar chimney power generating equipment with CFD technique

用Fluent软件对太阳能烟囱发电装置内的气流进行了数值模拟,获得了太阳能烟囱发电装置内气流流速、温度等分布,并将温度场模拟计算值和试验检测值进行了比较。结果表明:气流在集热棚中从四周向中部汇流是一个加速的过程;从地面到烟囱,随着高度的增加温度呈递减分布。温度分布模拟与试验检测结果的规律基本相似。但由于进行了稳态假设,也存在一定差别。数值模拟结果以集热棚中心呈对称分布。然而,由于集热棚南部接收的太阳辐射大于北部,在试验检测中南边的温度明显高于北边的温度,温度的峰值向南边偏移,呈不对称分布。

A numerical study with CFD has been carried out as to the air performance in the solar chimney equipment. The fluidity field and temperature field in the solar chimney were obtained, and the simulated temperatures were compared with measured temperatures. The results show that the flow rate of heated air increases from surrounding inlet radially to the center of the heat collector, and the temperatures decrease with the increasing of height from ground to chimney. To some extent, the simulated temperatures are in agreement with measured ones. However, the difference exists because some assumptions were applied in the numerical study. The simulated temperatures were symmetrical with the center of the geometry of collector due to steady assumption. But, with regard to the measured temperatures, the ones in the southern collector is higher than the ones in the northern collector, and the temperature peak moves to the south, not at the center of the collector, since the intensity of solar radiation is stronger on the southern collector than on the northern collector.