Performance Comparison of Solid and Porous Turbulent Promoters- A Numerical investigation

Abstract

Heat transfer rates are higher in turbulent flows compared to laminar flows. Increasing the turbulence intensity in the flow field will further increase the heat transfer rate. Turbulent promoters are flow obstructers placed in the flow field which induces turbulence and increase heat transfer rate within the fluid and in the solid-fluid interface. It causes the local heat transfer coefficient to increase and thereby increases the thermal performance of the system. The main drawback of using this kind of flow obstruction in the flow field is the pressure drop associated with it. In this paper, a numerical investigation of solid and porous turbulent promoters is conducted in a cooling channel. A single triangular-shaped promoter (solid and porous) at three different locations in the channel is investigated and results are obtained. Also, to study the geometrical influence of turbulent promoters three different geometries are compared. It is found that porous promoters can reduce the pressure drop to a considerable amount causing only a small reduction in heat transfer performance compared to solid promoters. Also found that the geometry and position of the turbulent promoters have a great influence on the pressure drop losses.