LATTICE BOLTZMANN SIMULATION OF BEHAVIOR OF VISCOELASTIC BODIES IN MICRO-CHANNEL FLOWS

建立了含粘弹性体两相流的晶格玻尔兹曼方法。用该方法对剪切流中物体的行为进行了数值模拟。无量纲剪切速率与物体变形能力之间的关系与已有的数值结果吻合较好。此外，还观察了履带履带的周期性旋转运动，证明了该方法的有效性。此外，还模拟了微通道中体的行为。根据物体的可变形性，发现处于平衡状态的物体向通道中心或在中心线与管壁之间横向移动。最后，对内部流体和周围流体的不同粘度比进行了模拟，并研究了粘度比对机体行为的影响。

A lattice Boltzmann method for two-phase flows containing viscoelastic bodies is developed. Numerical simulations of behavior of the bodies in shear flows are carried out by the present method. The relations between the dimensionless shear rate and the deformability of the body are in good agreement with available other numerical results. Also, the tank-treading motion, which is a periodic rotary motion like a caterpillar, is observed, and the validity of the present method is demonstrated. In addition, the behavior of the bodies in micro-channels is simulated. It is found that the body in equilibrium migrates toward the center of the channel or laterally between the centerline and the wall according to deformability of the body. Finally, these simulations are performed for various viscosity ratios of the internal fluid and the surrounding fluid, and the effect of the ratio on the behavior of the body is investigated.