Abstract In the present paper, the heat transfer of gravity-driven dense particle flow around a hexagonal tube is numerically studied. The velocity vector, time-averaged particle contacting number, particle contacting time and heat transfer coefficient of particle flow are carfully analyzed. Furthermore, the heat transfer performances of particle flow around a hexagonal tube, circular tube and elliptical tube are also compared. The results show that, the effect of top angle (Θ) on the particle flow around a hexagonal tube is noticeable. When Θ decreases from 120° to 60° (vout = 2 mm/s), the averaged heat transfer coefficient of particle flow would increase by 29.7%. The heat transfer performances of particle flow around different shape tubes are quite different. When Θ equals 60° (vout = 2 mm/s), as compared with circular tube, the averaged heat transfer coefficient of particle flow around an elliptical tube and a hexagonal tube increases by 17.2% and 20.5%, respectively.

中文翻译：

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六边形管周围重力驱动致密粒子流传热的数值研究

摘要 本文数值研究了重力驱动的密实粒子流在六角管周围的传热。详细分析了粒子流的速度矢量、时均粒子接触数、粒子接触时间和传热系数。此外，还比较了颗粒在六边形管、圆形管和椭圆管周围流动的传热性能。结果表明，顶角（θ）对六边形管周围颗粒流动的影响是显着的。当 Θ 从 120° 减小到 60°（vout = 2 mm/s）时，粒子流的平均传热系数将增加 29.7%。颗粒流在不同形状的管子周围的传热性能差异很大。当 Θ 等于 60° (vout = 2 mm/s) 时，与圆管相比，