Purpose

This paper aims to investigate the thermal performance of equivalent square and circular thermal systems and compare the heat transport and irreversibility of magnetohydrodynamic (MHD) nanofluid flow within these systems.

Design/methodology/approach

The research uses a constraint-based approach to analyze the impact of geometric shapes on heat transfer and irreversibility. Two equivalent systems, a square cavity and a circular cavity, are examined, considering identical heating/cooling lengths and fluid flow volume. The analysis includes parameters such as magnetic field strength, nanoparticle concentration and accompanying irreversibility.

Findings

This study reveals that circular geometry outperforms square geometry in terms of heat flow, fluid flow and heat transfer. The equivalent circular thermal system is more efficient, with heat transfer enhancements of approximately 17.7%. The corresponding irreversibility production rate is also higher, which is up to 17.6%. The total irreversibility production increases with Ra and decreases with a rise in Ha. However, the effect of magnetic field orientation (γ) on total EG is minor.

Research limitations/implications

Further research can explore additional geometric shapes, orientations and boundary conditions to expand the understanding of thermal performance in different configurations. Experimental validation can also complement the numerical analysis presented in this study.

Originality/value

This research introduces a constraint-based approach for evaluating heat transport and irreversibility in MHD nanofluid flow within square and circular thermal systems. The comparison of equivalent geometries and the consideration of constraint-based analysis contribute to the originality and value of this work. The findings provide insights for designing optimal thermal systems and advancing MHD nanofluid flow control mechanisms, offering potential for improved efficiency in various applications.

Graphical Abstract

中文翻译：

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磁性纳米流体热系统中热传输和不可逆性的基于约束的分析

目的

本文旨在研究等效方形和圆形热系统的热性能，并比较这些系统内磁流体动力（MHD）纳米流体流动的热传递和不可逆性。

设计/方法论/途径

该研究采用基于约束的方法来分析几何形状对传热和不可逆性的影响。考虑到相同的加热/冷却长度和流体流量，对两个等效系统（方形腔和圆形腔）进行了检查。分析包括磁场强度、纳米粒子浓度和伴随的不可逆性等参数。

发现

这项研究表明，圆形几何形状在热流、流体流动和传热方面优于方形几何形状。等效的循环热系统效率更高，传热增强约 17.7%。相应的不可逆生产率也较高，高达17.6%。总不可逆产量随着 Ra 的增加而增加，随着 Ha 的增加而减少。然而，磁场方向（ γ ）对总EG的影响较小。

研究局限性/影响

进一步的研究可以探索其他几何形状、方向和边界条件，以扩大对不同配置下热性能的理解。实验验证还可以补充本研究中提出的数值分析。

原创性/价值

本研究引入了一种基于约束的方法，用于评估方形和圆形热系统内 MHD 纳米流体流动的热传输和不可逆性。等效几何形状的比较和基于约束的分析的考虑有助于这项工作的原创性和价值。这些发现为设计最佳热系统和推进 MHD 纳米流体流动控制机制提供了见解，为提高各种应用的效率提供了潜力。

图形概要