基于格子Boltzmann方法的通道内液滴驱替研究

Lattice Boltzmann simulation of displacement of immiscible droplet in channel

用多相多组分格子Boltzmann模型中的伪势模型对单通道中壁面上液滴驱替进行模拟。主要目的是研究液滴与其外部流体分子质量比对驱替过程及临界邦德数的影响。首先用伪势模型模拟静态气泡,模拟结果与Young-Laplace定律吻合验证了模型的正确性。然后考虑流体与壁面作用力,对壁面上静态液滴润湿性进行模拟,得到参数g0w与接触角的关系。最后取g0w=0.04即液滴为接触角110°的非润湿性流体,加入质量力,考察液滴与其外部流体分子质量比不同时液滴驱替情况。模拟结果表明,当分子质量比增大时,液滴的界面张力减小,使液滴脱落的临界质量力减小,而临界邦德数增大。

The displacement of a droplet which adheres to the wall of a channel and subjects to body force was studied using a lattice Boltzmann multiphase-multicomponent model. The model was validated by simulating the Young-Laplace law and the result shows good agreement with the Young-Laplace law. Then the wettability of the droplet was simulated by taking account of the interactive force between the wall and the droplet. A linear relationship between parameter and contact angle was found. Finally, body force was taken into account and the study was focused on the effect of molecular mass ratio on the critical Bound number. Based on the simulated result, it is found that as the molecular mass body force become smaller, ratio becomes larger, however, the critical the surface tension of the droplet and the critical Bond number becomes lager.