Numerical Investigations of Flow Structure and Heat Transfer in Rectangular Narrow Channel with Longitudinal Vortex Generators Periodically Mounted on One Side

Abstract

Flow through an interrupted or enhanced heat transfer surface may cause the natural formation of vortices that can enhance local heat transfer. In this paper, Numerical investigations of flow structure and heat transfer in a horizontal rectangular narrow channel with periodically roughened mounted by rectangular bars as Longitudinal Vortex Generators (LVGs) was carried out for water. The unsteady Navier-Stokes equations and the energy equation have been solved by a finite volume code. The development of longitudinal vortex along the flow direction and its influence on heat transfer and flow were also presented in detail while keeping the aspect ratio of LVGs constant. The effect of LVGs’ mounted height, flow direction, mounted form on heat transfer performance and pressure drop were also conducted with Reynolds number ranging from 1.5×104 to 3.5×104 when the incidence angler of LVGs equal to 50°. It was found that the heat transfer performance in rectangular channel could be greatly enhanced by LVGs, and the mounted height of LVGs is greatly influence the effect of heat transfer enhancement, while the best height is 0.5mm.