The Effect of Square Splittered and Unsplittered Rods in Flat Plate Heat Transfer Enhancement

Authors

1 Engineering, Ferdowsi University of Mashhad

2 Mechanical Engineering, Ferdowsi University of Mashhad

3 Mecanical Engineering, erdowsi University of Mashhad

Abstract

A square splittered and unsplittered rod is placed in a turbulent boundary layer developed over a flat plate. The effect of the resulting disturbances on the local heat transfer coefficient is then studied. In both cases the square rod modifies the flow structure inside the boundary layer. As a result, a stagnation point, a jet and wake area are generated around the square rod, each making a contribution in disturbing the boundary layer and effect on the heat transfer coefficient from the neighboring flat plate. Effects of distance of square rod from the flat plate, inclusion of a splitter at the downstream of the rod, splitter length and its location relative to the square rod on local heat transfer coefficient in a variety of cases are studied. It is concluded that the effect of stagnation point is always to reduce the local heat transfer; the jet and wake both contribute on increasing heat transfer from the flat plate. The contribution of splitter on disturbing the boundary layer is not significant when compared to the effect of square rod when used alone. Splitter on its own contributes to controlling the wake effect and by changing the wake size and its structure reduces the wake effect on heat transfer. However these all depend on geometrical size and positioning of the splitter.

Keywords