圆管内纳米流体层流流动及强化传热的数值研究

Numerical Study on Laminar Flow of Nanofluids in Circular Tubes and Enhanced Heat Transfer

采用 AlO-水纳米流体作为工质,用数值模拟方法对其圆管内层流流体的流动及换热过程进行了可视化研究,在雷诺数 600~1 200 的范围内,分析了不同雷诺数下的流动换热效果及浓度对纳米流体层流传热性能的影响。结果表明:纳米流体中纳米颗粒的加入对流动通道内的速度和温度分布影响较大。随着纳米流体浓度的增加,流体的传热系数增大,换热效果增强,在研究范围内对流换热系数最大可增加 13.9%。相同浓度下随着雷诺数的增加,也有相似的变化趋势。

AlO-water nanofluid was used as working medium, and numerical simulation method was used to visualize the heat transfer process, and the fluid flow and heat transfer characteristics in a circular tube were analyzed. The influence of the concentration of nano-fluid on the flow and heat transfer characteristics was analyzed at Reynolds numbers ranging from 600 to1 200. The results showed that the addition of nano-particles in nano-fluid had little effect on the velocity and temperature distribution in the flow channel. With the increase of nano-fluid concentration, the heat transfer coefficient and flow resistance of the fluid increased, which had the effect of enhancing heat transfer. With the increase of Reynolds number at the same concentration,there was a similar change trend.