The multi-phase free convection of nano-encapsulated phase change material (PCM)/multi-walled carbon nanotube (MWCNT)–Fe₃O₄–water mixture inside an inclined porous half-annulus collector has been simulated using the Buongiorno's mathematical model. To create the buoyancy force, the internal Corrugated and outer cylinder wall are in the high constant hot flux as the hot wall and the constant temperature as the cold wall, respectively. The present study is investigated the effects of Rayleigh number (8 × 10² ≤ Ra ≤ 7 × 10⁴), Darcy number (Da = 0.01 and 1), inclined angle (0 ≤ ζ ≤ 90), and nanoparticles fraction ratio (0 ≤ fr ≤ 1) on flow pattern, temperature contours, nanoparticles distribution contours, dimensionless distribution of nanoparticles on the walls, and Nusselt number. Results show that the distribution of MWCNT inside the collector and on the walls is more uniform than Fe₃O₄ nanoparticles. The replacement of MWCNT with PCM is also analyzed to provide the more desired performance.

中文翻译：

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使用 Buongiorno 模型的波纹壁多孔半环集热器中纳米封装相变材料/多壁碳纳米管-Fe3O4-水混合物的三个分离相方程：布朗和热泳效应

使用 Buongiorno 的数学模型模拟了倾斜多孔半环集热器内纳米封装相变材料 (PCM)/多壁碳纳米管 (MWCNT)-Fe ₃ O _{4 -水混合物的多相自由对流。}为了产生浮力，内部波纹和外部圆柱壁分别处于高恒定热通量作为热壁和恒定温度作为冷壁。本研究考察瑞利数（8 × 10 ² ≤ Ra ≤ 7 × 10 ⁴）、达西数（Da = 0.01 和 1）、倾斜角（0 ≤ ζ ≤ 90)，以及流动模式、温度等值线、纳米粒子分布等值线、壁上纳米粒子的无量纲分布和努塞尔数的纳米粒子分数比 ( 0 ≤ fr ≤ 1 )。结果表明，MWCNT在集电极内部和壁上的分布比Fe ₃ O ₄纳米粒子更均匀。还分析了用 PCM代替MWCNT以提供更理想的性能。