入口段协同式翅片强化单相对流换热数值模拟

对二维平行平板通道入口段内设置协同式折流翅片的层流换热和流动特性进行了数值模拟。研究了翅片倾角以及通道长高比L／H对换热和阻力特性的影响。研究的Re数范围为100-1000。在翅片倾角β=0°-21.8°范围内, 通道内平均Nu数随翅片倾角β的增大而单调增大,随通道长度增大而单调减小。如果从相同泵功下强化效果来评价, 则是小倾角翅片较优,并且随Re数增大强化效果减弱。另外,分析表明,场的协同确实与换热率密切相关。

NUMERICAL STUDY ON THE SINGLE-PHASE HEAT TRANSFER IN CHANNEL ENTRANCE WITH A FLOW-INCLINING FIN

A numerical study has been performed on the flow and heat transfer in the entrance of a 2-D parallel plate channel. A flow-inclining fin is deployed on the wall surface in order to improve the field coordination and then to enhance the heat transfer. In the range of Re = 100-1000, the results reveal that the mean Nusselt number along the wall increases with the fin angle and decreases with the relative channel length. Evaluations under the condition of the same pump power consumption show that the channel with smaller fin angle is superior to those with larger fin angle. The enhancement effect diminishes as the Reynolds number increases. Additional analysis also ascertains the conjugated relation of the field coordination and the convective heat transfer.