Simulating liquid-vapor phase separation under shear with lattice Boltzmann method  

作　　者：WANG Ce XU AiGuo ZHANG GuangCai LI YingJun 

机构地区：[1]China University of Mining and Technology,Beijing 100083,China [2]National Key Laboratory of Computational Physics,Institute of Applied Physics and Computational Mathematics,Beijing 100088,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2009年第9期1337-1344,共8页中国科学：物理学、力学、天文学（英文版）

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos. 10775018 and 10702010);the National Basic Research Program of China (Grant No. 2007CB815105);the Science Foundations of LCP and CAEP

摘　　要：We study liquid-vapor phase separation under shear via the Shan-Chen lattice Boltzmann model. Besides the rheological characteristics, we analyze the Kelvin-Helmholtz (K-H) instability resulting from the tangential velocity difference of the fluids on two sides of the interface. We discuss also the growth behavior of droplets. The domains being close to the walls are lamellar-ordered, where the hydrodynamic effects dominate. The patterns in the bulk of the system are nearly isotropic, where the domain growth results mainly from the diffusion mechanism. Both the interfacial tension and the K-H instability make the liquid-bands near the walls tend to rupture. When the shear rate increases, the inequivalence of evaporation in the upstream and coagulation in the downstream of the flow as well as the role of surface tension make the droplets elongate obliquely. Stronger convection makes easier the transferring of material particles so that droplets become larger.We study liquid-vapor phase separation under shear via the Shan-Chen lattice Boltzmann model. Besides the rheological characteristics, we analyze the Kelvin-Helmholtz (K-H) instability resulting from the tangential velocity difference of the fluids on two sides of the interface. We discuss also the growth behavior of droplets. The domains being close to the walls are lamellar-ordered, where the hydrodynamic effects dominate. The patterns in the bulk of the system are nearly isotropic, where the domain growth results mainly from the diffusion mechanism. Both the interfacial tension and the K-H instability make the liquid-bands near the walls tend to rupture. When the shear rate increases, the inequivalence of evaporation in the upstream and coagulation in the downstream of the flow as well as the role of surface tension make the droplets elongate obliquely. Stronger convection makes easier the transferring of material particles so that droplets become larger.

关 键 词：lattice BOLTZMANN method the shan-chen model K-H INSTABILITY phase SEPARATION 

分 类 号：O351.2[理学—流体力学]