[关键词]
[摘要]
为了研究带有交错内肋微通道的流动和传热特性,采用数值模拟的方法分析了肋片的形状对微通道热力性能的影响,对比了矩形肋、菱形肋、三角形肋和圆形肋4种不同形状内肋结构的微通道和光滑矩形微通道的热力性能。结果表明:矩形肋、菱形肋、三角形肋和圆形肋微通道的努塞尔数Nu都大于光滑矩形微通道的努塞尔数Nu,最大值分别为光滑矩形微通道的2.59,2.71,2.90和2.48倍;肋片对微通道的传热特性具有显著的强化作用,这是由于流体在交错内肋的后方产生涡流,实现整个流场的全局强化传热,极大提升微通道传热特性;交错内肋的应用也增大了通道的摩擦系数,矩形肋、菱形肋、三角形肋和圆形肋微通道摩擦系数的最大值分别为光滑矩形微通道的8.66,7.96,17.50和5.96倍。
[Key word]
[Abstract]
In order to study the flow and heat transfer characteristics of microchannels with staggered internal ribs,the influence of the rib shape on the thermal performance of the microchannel was analyzed numerically. The thermal performance of the microchannels with four different shape ribs which are rectangular ribs, rhombus ribs, triangular ribs and circular ribs was compared with that of smooth rectangular microchannel. The results show that the Nusselt numbers of microchannels with rectangular ribs, rhombus ribs, triangular ribs and circular ribs are greatly larger than that of smooth rectangular microchannel. And the maximum Nusselt numbers of microchannels with four different shape ribs are 2.59, 2.71, 2.90 and 2.48 times of the smooth rectangular microchannel, respectively. Therefore, the ribs have a significant strengthening effect on the heat transfer characteristics of the microchannel. The vortices generated behind the staggered internal ribs are caused by the fluid, which realizes the overall enhanced heat transfer of the entire flow field and greatly improves the heat transfer characteristics of the microchannels. In addition, the application of staggered internal ribs also increases the frictional factor of the microchannels. The maximum frictional factors of rectangular ribs, rhombus ribs, triangular ribs and circular ribs are 8.66, 7.96, 17.50 and 5.96 times of smooth rectangular microchannel, respectively.
[中图分类号]
TK124
[基金项目]