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arXiv · 2507.14515

Numerical investigation of wake dynamics and heat transfer in MHD flows around confined triangular prisms

Amulya Sai Akkaladevi·Prabhat Kumar·Sachidananda Behera
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Abstract

This study numerically investigates the flow evolution and heat transfer characteristics of an electrically conducting fluid over triangular prisms confined between two parallel plates with a heated bottom plate under the influence of a magnetic field. The research focuses on the three-dimensional behavior of MHD flows at low Hartmann numbers ($Ha$), exploring how obstacle orientation and mixed convection influence flow dynamics and heat transfer. Three-dimensional simulations are performed using an in-house MHD solver in OpenFOAM at a constant channel height based Reynolds number ($Re_{h}=600$). The combined effects of Richardson number ($Ri$) and $Ha$ on wake dynamics and heat transfer are analyzed for three triangular prism orientations. The results reveal that increasing $Ha$ promotes flow two-dimensionality, while higher $Ri$ enhances three-dimensionality. Three wake instability modes (Mode A, B, and C) are identified. Orientation 2 exhibits the lowest mean drag coefficient at $Ha=0$, $Ri=5$, while the highest mean lift coefficient is observed at $Ha=0$, $Ri=0$. Orientation 3 achieves the highest heat transfer rate, with an average Nusselt number of $21.05$ at $Ha=25$, $Ri=5$, and consistently outperforms the other orientations in heat transfer across various $Ha$ and $Ri$ conditions. These findings highlight the strong coupling between wake dynamics and heat transfer, offering insights for optimizing MHD flows in practical applications.

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Amulya Sai Akkaladevi, Prabhat Kumar, Sachidananda Behera. 2025-07-19. Numerical investigation of wake dynamics and heat transfer in MHD flows around confined triangular prisms. https://arxiv.org/abs/2507.14515

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