ABSTRACT Thermal characteristics of water in a ground U-tube with twisted tape inserts were addressed. At inlet temperatures of 60°C to 75°C, and Reynolds numbers of 3000 to 9000, the surface heat transfer coefficients for water with twisted tapes ranged from 442 to 897 W m−2 K−1, which were higher than that in smooth tube, 384–810 W m−2 K−1. Average convective heat transfer coefficient for the smooth tube in sand/graphite blend ameliorated by 36% compared to that in sand. Average apparent thermal diffusivities of sand/graphite at hot end temperature of 70°C rose by about 17% compared to sand.

中文翻译：

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砂/石墨回填材料中带有扭曲带的磨削 U 形管的热性能

摘要解决了带有扭曲带插入物的接地 U 形管中水的热特性。在入口温度为 60°C 至 75°C，雷诺数为 3000 至 9000 时，带扭曲带的水的表面传热系数为 442 至 897 W m-2 K-1，高于光滑带水的表面传热系数。管，384–810 W m−2 K−1。与砂相比，砂/石墨混合物中光滑管的平均对流传热系数提高了 36%。与砂相比，砂/石墨在 70°C 热端温度下的平均表观热扩散率提高了约 17%。