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该文以粗砂土为研究对象,对粗砂土在不同水位条件下流动与传热情况进行研究。建立粗砂土三维模型,采用有限体积法进行数值计算,并利用恒温实验平台进行验证。结果表明:在正常条件下粗砂土内以对流换热为主,其流线呈顺时针方向流动;粗砂土内水气交界面处存在温度场和流态的突变,出现了半涡形结构和高于壁面温度的现象;瑞利数对粗砂土对流换热影响显著,与Nu数呈指数关系;在实验中温度呈非线性变化,各测点温度值分布为4层2区;模拟值与实验值基本一致,三维模型具有更高的准确度。
In this paper, the coarse sand as the research object, the coarse sand in different water conditions flow and heat transfer conditions are studied. The three-dimensional model of coarse sand was established, and the finite volume method was used for numerical calculation. The experiment was carried out with a constant temperature experimental platform. The results show that under normal conditions, the convective heat transfer is the main factor in the coarse sand, and its streamline flows in a clockwise direction. There is a sudden change in temperature field and fluid regime at the interface between the water and gas in the coarse sand, Structure and temperature higher than the wall temperature. The Rayleigh number has a significant effect on the convective heat transfer of coarse sand and exponential relationship with the Nu number. In the experiment, the temperature changes nonlinearly, The simulated values are basically consistent with the experimental values, and the three-dimensional model has higher accuracy.