화학공학소재연구정보센터
International Journal of Heat and Mass Transfer, Vol.54, No.1-3, 482-489, 2011
Numerical study of turbulent slot jet impingement cooling on a semi-circular concave surface
An investigation of the flow field and heat transfer characteristics of a slot turbulent jet impinging on a semi-circular concave surface with uniform heat flux has been carried out numerically in this study. The turbulent governing equations are solved by a control-volume-based finite-difference method with a power-law scheme and the well-known k-epsilon turbulence model and its associate wall function to describe the turbulent structure. In addition, a body-fitted curvilinear coordinate system is employed to transform the physical domain into a computational domain. Numerical computations have been conducted with variations of jet exit Reynolds number Re-2B (5920 <= Re-2B <= 23,700), dimensionless jet-to-surface distance H/B (0.5 <= H/B <= 12), dimensionless jet width B/D (0.033 <= BID <= 0.05) and the heat flux q" (1663 W/m(2) <= q" <= 5663 W/m(2)). The theoretical model developed is validated by comparing the numerical predictions with available experimental data in the literature. The variations of local Nusselt numbers along the semi-circular concave surface decrease monotonically from its maximum value at the stagnation point. The numerical results show that the local Nusselt numbers are reasonably predicted with a maximum discrepancy within 15%. As the Reynolds number fixes, the effect of the impingement distance (H/B) on the average Nusselt (Nu(avg)) is not significant except at low H/B = 0.5. This study provides fundamental insight into turbulent slot jet impingement cooling on the semi-circular concave surface. (C) 2010 Elsevier Ltd. All rights reserved.