Enhanced Heat Transfer in a Vertical Heated Channel by Incorporation of Inclined Plates

This study aims to investigate fluid flow and heat transfer behaviors under laminar mixed convective conditions in a vertical heated channel with plates attached to the heated wall in order to enhance the cooling channel. Simulations were conducted using the finite volume method through the OpenFoam © open-source code. The analysis focused on three key physical parameters: Reynolds number varying from ۲۰۰ to ۱۴۰۰, Grashof number set at ۱۰۵ and ۲×۱۰۵, and three plate tilt angles (γ = ۳۰°, ۶۰°, and ۹۰°), with a fixed plate height of hp = ۰.۳ and a constant plate spacing of D = ۱. The objective was to assess their effects on thermal and flow behaviors in both steady-state and self-sustained oscillatory flow. The results were presented as dimensionless isotherm contours and streamlines, accompanied by the Nusselt number and friction factor ratios. Findings indicate that both the friction factor and Nusselt number ratios increase as Reynolds number and plate tilt angles increase, while they decrease as the Grashof number increases. The flow translates to a self-sustained oscillatory state at moderate Reynolds numbers (below ۱۰۰۰ for γ = ۶۰° and ۹۰°, below ۱۲۰۰ for γ = ۳۰°). Moreover, as the flow bifurcates to an unsteady state, the Nusselt number significantly increases and can reach up to ۱۸%, ۵۴% and ۶۰% for γ = ۳۰°, ۶۰° and ۹۰°, respectively, compared to the channel without plates. The unsteady flow pattern contributes to enhancing the heat transfer by disturbing the near-wall region. Notably, the plate tilt angle of γ = ۳۰° achieves an optimal balance between enhancing heat transfer efficiency and reducing flow resistance. From these results, it can be concluded that this study is useful for the design efficiency of electronic cooling systems and heat exchangers that can provide maximum heat transfer with minimum flow resistance.

کلیدواژه ها:

Mixed convection ، heat transfer enhancement ، Unsteady Flow ، Plates ، Channel