改进的浸入边界-晶格Boltzmann法的蠕动流分析
Study on the Peristaltic Flow Based on a Modified Immersed Boundary-Lattice Boltzmann Method

基于改进的浸入边界-晶格Boltzmann方法研究蠕动流问题，采用晶格Boltzmann法描述流场，用改进的浸入边界法实现管壁运动 流体流动之间的相互作用，将变形管壁的运动速度作为速度源引入晶格Boltzmann方程，代替了传统浸入边界-晶格Boltzmann法中固态变形力与流体速度之间的转换。分析了管道内蠕动流场的分布情况，研究了各相关参数如振幅比、频率、液体黏度以及波数对流量的影响，数值结果与已有的结果进行了对比，证实了本研究方法的合理性与有效性。
In this paper, peristaltic flow in a tube due to the waves of contraction is studied applying a modified immersed boundary-lattice Boltzmann method. The lattice Boltzmann method is used to describe the flow filed, and the modified immersed boundary method is used to couple the moving boundaries to the surrounding fluid. This method introduces the velocity induced by the flexible tube wall into the lattice Boltzmann equation, which replaces the conversion between the fluid velocity and the force induced by the deformation of the moving boundaries in the traditional immersed boundary-lattice Boltzmann method. We analyze the streamlines and velocity distribution, then systematically investigate the effects of variation of the relevant parameters such as the amplitude ratio and frequency of the traveling wave, viscosity of the fluid and wavenumber on the flow of the peristaltic tube. The comparison between the simulative and existing results shows that the method is reasonable and effective.