A numerical study on the heat transfer characteristics of two-dimensional inclined impinging jet

摘要

A two-dimensional numerical study has been applied to predict the heat transfer rate in the turbulence, unconfined, and submerged impinging jet discharged from a slot nozzle to flat and inclined plate by using commercial finite volume code FLUENT. The Reynolds in range of 4000-16000, the nozzle exit-to-plate spacing (H/D) in the range of 4-10 and inclination angle of air jet and plate in range of 40-90 has been considered. The constant heat flux of 100 w / m/sup 2/ was set to impinging plate. Two k-/spl epsiv/ RNG and Reynolds stress models by using the Enhanced Wall Treatment were used in all cases and local Nusselt number on the impinging jet plate was compared with experimental results. The Enhanced Wall Treatment by solving the fully turbulence region and viscous sublayer and using a single function improves effect of pressure gradients and thermal effects. The heat transfer rate in flat plate impinging jet in stagnation point is in its maximum value and then decreases along the wall. In the inclined impinging jet by movement of the stagnation point to uphill side maximum heat transfer rate location moves to uphill side of the plate but decreasing of Nusselt number is more gradually in downhill side. The numerical results predict the heat transfer rate in flat plate impinging jet by less than 10% difference in comparison with experiments however for inclined impinging jet in different HID, the prediction shows 5-20% difference.