USE OF WAISTED TRIANGULAR-SHAPED BAFFLES TO ENHANCE HEAT TRANSFER IN A CONSTANT TEMPERATURESURFACED RECTANGULAR CHANNEL

Abstract

The purpose of the present computational fluid dynamic analysis is to investigate the turbulent flow and heat transfer characteristics of air inside a constant temperature-surfaced rectangular cross section channel, where two waisted triangular-shaped baffles (WTBs) were placed in opposite walls. The aim at using the left and right wall-mounted solid-type WTBs is to create recirculation cells having a significant influence on the flow field leading to higher thermal transfer rate in the whole domain investigated. The governing equations with the associated boundary conditions were discretized using the Finite Volume Method (FVM). The SIMPLEC-algorithm was used for the convective terms in the solution equations. As expected, the largest variations in the Nusselt number and friction loss occur in the regions near to the WTBs, due to the strong velocity gradients in those regions. Some numerical results were compared with those obtained by the experiment in the literature. This comparison shows that there is a qualitative agreement as well as a very good concordance between the two results. The current originality lies in the geometric shape of the baffles inside the channel. This study can be a real application in the field of shell-and-tube heat exchangers and air plan solar collectors.

Keywords

• Aerodynamics
• CFD
• Fluid dynamics
• Engineering and industrial applications
• Heat exchangers
• Waisted baffles.