Turbulent-Heat-Flux and Temperature-Variance Budgets in a Single-Rib Mounting Channel

Abstract

Heat transfer and fluid flow in a single-rib mounting channel were investigated by directly solving Navier-Stokes and energy equations. The flow and thermal fields were considered to be fully developed at the inlet of the channel, and the simulation was made for spatial advancement of turbulent heat transfer. The Reynolds number based on the friction velocity at the inlet and the channel half width was 150. The Prandtl number was 0.71. The budgets for turbulent heat fluxes and temperature variance at various sections were presented and were investigated, which would be useful for testing and developing turbulence models. Near a circular vortex in front of the rib, pressure diffusion terms made an important contribution. Remarkable production terms were generated near a reattachment point. Production and dissipation terms were not dominant in front of and above the rib, and a time scale ratio exceeded 2.0 in the region.

Keywords

• turbulent flow
• heat transfer enhancement
• direct numerical simulation
• rectangular rib
• turbulent heat flux budget
• temperature variance budget