化工学报2018，Vol.69Issue(6)：2373-2379,封4,8.DOI:10.11949/j.issn.0438-1157.20171311
球形胶囊内约束熔化过程的LBM模拟
Numerical simulation of constrained melting inside spherical capsule by lattice Boltzmann method
摘要
Abstract
Phase change materials (PCMs) are mainly used to provide high storage densities. The spherical geometry is one of the most interesting cases for heat storage applications. The present study used the lattice Boltzmann method (LBM) to investigate constrained melting process of PCMs in a spherical capsule, which can be useful for the study on phase change phenomenon of microencapsulated PCM slurry in the future. The phase interface is traced by updating the total enthalpy, while the moving interface is treated by the immersed moving boundary scheme. The computational results of the melting process of PCMs are analyzed at different scales. The numerical simulations at macro-scale are compared with the published experimental data, and the results clearly show that the thermal stratification is in the upper of the sphere capsule while the waviness phase front is at the bottom of the solid PCM. Quantitative analysis of the temperatures at nine points, eight points along the vertical axis and the other one near the inner shell, further indicates the existence of chaotic convective motion at the bottom of the sphere capsule. In addition, the effect of the natural convection on the melting process is reduced as the decrease of capsule sizes. When the diameter of capsule is less than 3 mm, the natural convection can be ignored.关键词
相变/多尺度/数值模拟/热力学/格子Boltzmann方法Key words
phase change/multiscale/numerical simulation/thermodynamics/lattice Boltzmann method分类
数理科学引用本文复制引用
林琦,王树刚,王继红,宋双林..球形胶囊内约束熔化过程的LBM模拟[J].化工学报,2018,69(6):2373-2379,封4,8.基金项目
国家自然科学基金项目(51678102, 51508067). supported by the National Natural Science Foundation of China (51678102, 51508067). （51678102, 51508067）
