TURBULENT FLOW AND HEAT TRANSFER FROM CONFINED MULTIPLE IMPINGING SLOT JETS

Abstract

Results are presented of numerical simulation of the steady turbulent flow field and impingement heat transfer due to three and five turbulent heated slot jets discharging normally into a confined channel. Both the Lam-Bremhorst low Reynolds number and the standard high Reynolds number versions of κ-ε turbulence models were used to model the turbulent multijet flow. A control volume based finite difference method was employed to solve the governing mass, momentum, turbulent kinetic energy, turbulent kinetic energy dissipation rate, and energy equations iteratively. The parameters studied were the jet Reynolds number (5000 < Re < 20,000), nozzle-to-impingement surface spacing (2.5 < H/W < 7.5), and nozzle-to-nozzle centerline spacing (S/W = 5, 8). From the present study, it was found that the Lam-Bremhorst model overestimates the normalized heat transfer coefficient Nux, while the standard high Reynolds number model underestimates it.