三维多孔吸液芯毛细特性孔隙尺度格子Boltzmann模拟  

Three-Dimensional Lattice Boltzmann Simulation of Capillary Performance in a Porous Wick at Pore Scale

作　　者：李健[1] 郑雯瀚 洪芳军[1] LI Jian;ZHENG Wen-Han;HONG Fang-Jun(School of Mechanical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学机械与动力工程学院,上海200240

出　　处：《工程热物理学报》2022年第3期758-762,共5页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.51776121)。

摘　　要：通过改进后的QSGS方法构造了三维复杂多孔吸液芯结构,采用格子Boltzmann方法和GPU并行算法,数值模拟了孔隙尺度下多孔吸液芯毛细抽吸两相传输动态特性,并探讨了表面润湿性和孔隙率对两相界面分布和毛细性能的影响。研究结果表明,对于三维复杂结构多孔吸液芯,毛细抽吸过程中两相界面不规则性、分布不均匀性程度较大,孔尺度效应显著。在一定范围内,随着多孔表面润湿性的增强,吸液芯孔隙率的降低,毛细作用相应增强,吸液芯内液体抽吸速率增加,最大吸液量逐步增大,毛细性能也随之提高。A lattice Boltzmann model(LBM) is used to numerically investigate on the pore-scale two-phase flow of capillary pumping process in a three-dimensional heterogeneous porous wick generated by an improved Quartet structure generation set(QSGS) method. The parallel LBM algorithm based on the Graphics Processing Unit(GPU) is adopted to reduce computation time. Effects of surface wettability and wick porosity on two-phase interface distributions and capillary performance are examined in detail. The numerical results indicate that the two-phase interface shape and distribution in three-dimensional random porous wick is very irregular and asymmetric. As surface wettability raises and wick porosity reduces, capillary action provided by porous microstructure enhances, liquid penetration rate increases and steady-state maximum volume of liquid imbibed into the wick increases, i.e., the capillary pumping performance is improved.

关 键 词：多孔吸液芯 两相流 毛细抽吸 格子BOLTZMANN 孔隙尺度 

分 类 号：O363.2[理学—流体力学]