Numerical Study Of Flow And Heat Transfer In Narrow Channel Influenced By Circular Arc Dimple

Through the narrow channel is an effective means of heat transfer, the circular arc dimple (it is named dimple)surface in narrow channel would enhance heat transfer. The technical of dimple is a new development which used for enhancing heat transfer and now it used in many field. we develop the numerical calculation to the flow channel with a dimple and analyze the local heat transfer characteristics ,and also analyze its flow and heat transfer according the field of velocity and temperature. Present thesis, in the first, built up the physical model of the rectangular channel with the arrays of dimples on the bottom surface, on the basis of actual flow and heat transfer in the channel, brought forward the hypothesizes and built up the math model.. In the math model RNG k ?εturbulent model was employed, and SIMPLE algorithm was applied to resolve the pressure-velocity coupling. This model was checked up by N. K. Burgess's experimental data. We calculated the flowing and heat transfer in the narrow channel with the dimple surface when double dimple has difficult distance. Research shows that the heat transfer of dimple surface is increased when we enlarged the distance. But there is a critical point of the distance. Before this point, the heat transfer is increased when enlarged the distance, but after it, it would be weaker. of course the different flow channel has itself critical point . We should apply it according the actually experiment. To the flow channel with many much dimples, the research shows that the dimple would increase the numerical of both heat transfer and pressure drops in channel .The number of the dimples would greatly influence the heat transfer in the narrow channel. The heat transfer would augment with the increase of the numerical of the dimple in channel. But when it arrives to one point, it would be weaker. The study to this condition also shows influence of the distance of the dimples to heat transfer. The research of the mechanical of the heat transfer in narrow channel with dimples and the factor of the heat transfer in this channel will provide for farther investigation on the dimpled channel.