This work presents a numerical analysis for exploring heat transfer phenomena in an enclosed cavity using magnetohydrodynamics natural convection. Because of the numerous real-world applications of nanofluids and hybrid nanofluids in industrial and thermal engineering developments, hybrid nanofluids are used as fluid mediums in the fluid field. A hexagonal-shaped heat exchanger is taken with two circular surfaces along the middle part. The upright circular surface acts as a homogeneous heat source, while the lower circular surface functions as a heat sink. The remaining portions of the adjacent walls are thermally insulated. The copper (Cu) and titanium dioxide (TiO₂) nanoparticles are suspended into water to make a hybrid nanofluid. For solving the corresponding governing equations, the weighted-residual finite element method is applied. To explain the major outcomes, isotherms, streamlines, and many others 2D and 3D contour plots are involved graphically with a physical explanation for different magnitudes of significant parameters: Rayleigh number , Hartmann number , and nanoparticle volume fraction . The novelty of this work is to apply response surface methodology on the natural convective hybrid nanofluid model, to visualize 2D and 3D effects, and to study the sensitivity of independent parameters on response function. Due to the outstanding thermal properties of the hybrid nanofluid, the addition of Cu and TiO₂ nanoparticles into H₂O develops the heat transfer rate to 35.85% rather than base fluid. Moreover, a larger magnitude of Ra and the accumulation of mixture nanoparticles result in the thermal actuation of a hybrid nanofluid. With greater magnetic impact, an opposite response is exhibited.

中文翻译：

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使用 RSM 对含有混合纳米流体的自然对流换热器进行数值模拟和灵敏度分析

这项工作提出了利用磁流体动力学自然对流探索封闭腔体中传热现象的数值分析。由于纳米流体和混合纳米流体在工业和热工程开发中的大量实际应用，混合纳米流体被用作流体领域中的流体介质。换热器呈六边形，中间有两个圆形表面。直立的圆形表面充当均匀热源，而下部圆形表面充当散热器。相邻墙的其余部分是隔热的。将铜（Cu）和二氧化钛（TiO ₂）纳米颗粒悬浮在水中以制成混合纳米流体。为了求解相应的控制方程，采用加权残差有限元法。为了解释主要结果、等温线、流线图和许多其他 2D 和 3D 等高线图，以图形方式涉及不同大小的重要参数的物理解释：瑞利数,哈特曼数，和纳米颗粒体积分数。这项工作的新颖之处在于将响应面方法应用于自然对流混合纳米流体模型，可视化 2D 和 3D 效应，并研究独立参数对响应函数的敏感性。在H ₂ O中添加Cu和TiO ₂纳米粒子比基础流体的传热率提高到35.85%。此外，更大的Ra量级和混合物纳米颗粒的积累会导致混合纳米流体的热驱动。磁力影响越大，则表现出相反的响应。