Abstract A numerical investigation of the free convection of the Al2O3/water nanofluid was carried out in a square cavity. The cavity was tilted and exposed to a constant horizontal magnetic field. Radiation also occurred in the cavity, and entropy generation was also investigated. The left-hand and right-hand walls of the cavity were kept at a fixed temperature (Tc), while the upper and lower walls were insulated. A circular baffle with a radius of R and a temperature of Th was placed in the middle of the cavity. According to the results, amplifying the Rayleigh number (Ra) improved the Nusselt number (Nu) by 4.5 times. Amplifying the Ra also promoted entropy generation but diminished the Bejan number (Be). The heat transfer rate and generated entropy increased also by amplifying the aspect ratio. An amplification of the Hartmann number (Ha) reduced the heat transfer rate and generated entropy by 45% and 35%, respectively. Furthermore, Be was also augmented by growing the Ha. The maximum entropy generation and Be were observed at 0 and 60° inclination angles, respectively. Incorporating heat transfer by radiation and adding nano-particles to the base fluid increased both the heat transfer rate and entropy generation.

中文翻译：

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热辐射和磁场效应下倾斜方腔内圆形挡板周围纳米流体的自然对流和熵产生

摘要 在方腔中对Al2O3/水纳米流体的自由对流进行了数值研究。腔体倾斜并暴露在恒定的水平磁场中。腔中也发生辐射，并且还研究了熵的产生。腔的左手和右手壁保持在固定温度 (Tc)，而上壁和下壁是隔热的。一个半径为R、温度为Th的圆形挡板放置在腔体的中间。根据结果​​，放大瑞利数 (Ra) 将努塞尔数 (Nu) 提高了 4.5 倍。放大 Ra 也促进了熵生成，但减少了 Bejan 数 (Be)。通过放大纵横比，传热率和产生的熵也增加了。哈特曼数 (Ha) 的放大使传热率和产生的熵分别降低了 45% 和 35%。此外，Be 还通过增加 Ha 得到增强。分别在 0°和 60°倾角处观察到最大熵产生和 Be。通过辐射进行传热并将纳米粒子添加到基液中，可以提高传热率和熵的产生。