Impact of inclined and perforated baffles on the laminar thermo-flow behavior in rectangular channels

In this paper, incompressible thermo-flow is simulated for a channel and with and without baffles. A baffle is connected to the channel from different angles. The effect of perforated inclined baffles on the flow pattern and heat transfer in a channel investigated. The computations are based on the finite element method, Galerkin scheme, and Newton–Raphson iterative method have been implemented. The flow regime was assumed to be laminar. Results show that the use of perforated baffles leads to an increase in the Nusselt number and minimized friction factor in comparison to the plain ones. The numerical results are compared with the available solutions in the literature. The defined efficiency of the baffle is obtained for various baffle types, baffle’s angle, Reynolds number, and baffle’s ratios. The optimum angle of the baffle inclinations was obtained. It was found that perforated baffles demonstrate show superior performance when compared with plain counterparts. Also, there is local heat transfer enhancement at the downstream of the stepped baffle caused by the impinging effect of flow, which is even more significant when baffle height becomes higher or the Reynolds number elevates. Obtained results show that a 135° perforated baffle is a better choice as it enhances the heat transfer with a minimal friction factor.