Hot cylinders within the cavity can find diverse thermal applications, ranging from electronic devices and heat exchangers to solar systems, nuclear reactors, and the thermal design of passive cooling systems. Consequently, considering the use of phase change materials (PCM) close to hot cylinders emerges as a viable method for both cooling and storing thermal energy. In this work, two hot cylinders are arranged vertically and horizontally in the nano-enhanced phase change material (NePCM) trapezoidal enclosure with varying angles. The novelty of the current study lies in the fact that no prior research has explored the impact of hot cylinders arrangement on the melting process of a NePCM within a trapezoidal cavity, considering various inclination angles. The fixed grid, adaptive mesh refinement, and enthalpy-porosity method are used to model the melting flow. The numerical results indicate that the trapezoidal enclosure with vertically arranged hot cylinders exhibits better thermal performance than the other configuration. It is also found that the full melting time for both arrangements is minimum when the angle of the trapezoidal enclosure is . The reduction in full melting times for the vertical and horizontal arrangements of this angle are 25.3% and 29.6%, respectively, compared to the trapezoidal enclosure with . Moreover, the NePCM with the graphite nanoplatelets (GNPs) of has the shortest melting time for . As future research, further exploration into the complexities of non-Newtonian NePCM flow can be pursued. Additionally, there is potential to explore modifying the cylinders' geometry into elliptical forms, encompassing a range of aspect ratios.

中文翻译：

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带热缸的梯形外壳内 NePCM 熔化流动分析：热缸配置和倾斜角度的影响

腔体内的热缸可以找到多种热应用，从电子设备和热交换器到太阳能系统、核反应堆以及被动冷却系统的热设计。因此，考虑在热气缸附近使用相变材料（PCM）成为冷却和储存热能的可行方法。在这项工作中，两个热圆柱体以不同角度垂直和水平排列在纳米增强相变材料（NePCM）梯形外壳中。本研究的新颖之处在于，之前没有研究考虑到不同的倾斜角度，探索热缸布置对梯形腔内 NePCM 熔化过程的影响。采用固定网格、自适应网格细化和焓孔隙率法对熔化流动进行建模。数值结果表明，具有垂直排列热缸的梯形外壳比其他配置表现出更好的热性能。还发现，当梯形外壳的角度为 时，两种布置的完全熔化时间最短。与具有 的梯形外壳相比，该角度的垂直和水平布置的完全熔化时间分别减少了 25.3% 和 29.6%。此外，具有石墨纳米片（GNP）的NePCM具有最短的熔化时间。作为未来的研究，可以进一步探索非牛顿 NePCM 流的复杂性。此外，还有可能探索将圆柱体的几何形状修改为椭圆形，涵盖一系列长宽比。