Abstract
A numerical study was conducted to investigate the heat transfer performance when a wing type vortex generator is installed in the laminar and turbulent channel flows. The turbulence induced by the wing enhances the turbulent heat transfer more effectively than the Reynolds stress. This is caused by the fact that the apparent eddy diffusivity of momentum transfer is remarkably reduced in the back flow of wing. In that region, a strong inward flow exists because of the longitudinal vortices induced by the wing and of the flow from the hall on the bottom wall of upper channel. The Reynolds stress is suppressed noticeably since the fluid with small momentum is transferred to the wall by the inward flow, which results in the effective heat transfer enhancement with small turbulent drag.
