This work is devoted to the study of steady thermocapillary-buoyant convection in a system of two horizontal superimposed immiscible liquid layers filling a lateral heated thin annular pool.The governing equations are...This work is devoted to the study of steady thermocapillary-buoyant convection in a system of two horizontal superimposed immiscible liquid layers filling a lateral heated thin annular pool.The governing equations are solved using an asymptotic theory for the aspect ratios ε→ 0.Asymptotic solutions of the velocity and temperature fields are obtained in the core region away from the cylinder walls.In order to validate the asymptotic solutions,numerical simulations are also carried out and the results are compared to each other.It is found that the present asymptotic solutions are valid in most of the core region.And the applicability of the obtained asymptotic solutions decreases with the increase of the aspect ratio and the thickness ratio of the two layers.For a system of gallium arsenide （lower layer） and boron oxide （upper layer）,the buoyancy slightly weakens the thermocapillary convection in the upper layer and strengthens it in the lower layer.展开更多
基于COMSOL Multiphysics软件的非等温流动模块建立了一种适用于熔融池的仿真计算模型。采用相变材料模型模拟实验中的非共晶摩尔比例20%NaNO_(3)-80%KNO_(3)熔融物,通过将实验台架顶端封闭腔的辐射换热转化为表面对外界环境辐射边界条...基于COMSOL Multiphysics软件的非等温流动模块建立了一种适用于熔融池的仿真计算模型。采用相变材料模型模拟实验中的非共晶摩尔比例20%NaNO_(3)-80%KNO_(3)熔融物,通过将实验台架顶端封闭腔的辐射换热转化为表面对外界环境辐射边界条件,对COPRA(COrium Pool Research Apparatus)实验的湍流场和传热相变过程进行了仿真模拟。仿真结果表明:熔融池内除了存在明显的自然对流外还存在大量的涡流,且在稳态下熔融池内会出现明显的热分层结构。受自然对流和重力影响,冷却壁面附近熔融物结壳的厚度沿冷却壁面随熔融池圆弧壁面径向角度增加而减小。展开更多
基金supported by the National Natural Science Foundation of China (50776102)the Fundamental Research Funds for the Central Universities (CDJXS1041148)
文摘This work is devoted to the study of steady thermocapillary-buoyant convection in a system of two horizontal superimposed immiscible liquid layers filling a lateral heated thin annular pool.The governing equations are solved using an asymptotic theory for the aspect ratios ε→ 0.Asymptotic solutions of the velocity and temperature fields are obtained in the core region away from the cylinder walls.In order to validate the asymptotic solutions,numerical simulations are also carried out and the results are compared to each other.It is found that the present asymptotic solutions are valid in most of the core region.And the applicability of the obtained asymptotic solutions decreases with the increase of the aspect ratio and the thickness ratio of the two layers.For a system of gallium arsenide （lower layer） and boron oxide （upper layer）,the buoyancy slightly weakens the thermocapillary convection in the upper layer and strengthens it in the lower layer.
文摘基于COMSOL Multiphysics软件的非等温流动模块建立了一种适用于熔融池的仿真计算模型。采用相变材料模型模拟实验中的非共晶摩尔比例20%NaNO_(3)-80%KNO_(3)熔融物,通过将实验台架顶端封闭腔的辐射换热转化为表面对外界环境辐射边界条件,对COPRA(COrium Pool Research Apparatus)实验的湍流场和传热相变过程进行了仿真模拟。仿真结果表明:熔融池内除了存在明显的自然对流外还存在大量的涡流,且在稳态下熔融池内会出现明显的热分层结构。受自然对流和重力影响,冷却壁面附近熔融物结壳的厚度沿冷却壁面随熔融池圆弧壁面径向角度增加而减小。
