格子玻尔兹曼方法(LBM)及其在微通道绕流中的应用

Numerical Simulation of Flow around a Cylinder in Micro-Channel by the Lattice Boltzmann Method

介绍了格子玻尔兹曼方法基本理论与计算方法,并建立了D2Q9计算模型,对宏观尺度及微通道中的非稳态绕流进行了数值模拟,得到了绕流过程的速度分布和涡量分布等信息,对流场结构、固体阻力、尾涡脱落等变化规律进行了分析。结果表明,格子玻尔兹曼方法以其计算稳定、效率高等优势能够应用于微反应器领域的数值模拟;同等液相停留时间条件下,微反应器中的圆柱绕流湍动程度明显降低,未形成周期性涡流,流动更加均匀稳定,有助于实现化学反应的精确控制。

The lattice Boltzmann method,its most important model lattice BGK and the boundary condition were introduced briefly.Using LBM,numerical simulation of flow around a cylinder in micro-channel was computed.The results included the velocity and vorticity distribution,the flow resistance,vortex formation and periodic shedding.The results showed that LBM had a stable and reliable computation performance and high efficiency,and could be used to investigate the fluid dynamics in micro-reactors.The turbulence around the cylinder in the micro-reactor decreased,and no periodic eddy current was formed.The flow was more uniform and stable,which was helpful to control the chemical reaction accurately.