管间距对通道内竖直排列水平双管自然对流的影响

分析了管间距对圆管自然对流的影响,为解决河道热扩散问题提供理论依据,具有实际的应用价值。抽象出通道内竖直排列水平双管的模型,采用SIMPLE算法模拟了不同管间距下的自然对流现象。结果表明:随着管间距S的增大,两管之间的流动逐渐增强,上管的换热明显增强,Ra越大,增强效果越明显。此外,研究了管间距S对烟囱效应的影响。结果表明:随着S的增大,流经通道的流体流量增加,即烟囱效应增强。

Effect of pipe spacing on nature convection flow around a pair of horizontal cylinders in a channel

The paper analyzed the influence of pipe spacing on natural convection of cylinders so as to provide theory reference for solving thermal diffusion problem of river.The result has certain application value.The model of a pair of horizontal cylinders in a channel is abstracted. It introduced SIMPLE to simulate the natural convection under different longitudinal pitch. The results showed that with the increase of pipe spacing S,the flow between two horizontal cylinders become stronger.The heat transfer around the upper cylinder is enhanced obviously, the more the Ra,the more evident the enhancing effect.In addition,the paper investigated the influence of longitudinal pitch ratios on chimney effect.The volume flow rate in the channel increases with the increase of S. The chimney effect is strengthen.