相互碰撞的圆粒子在竖直通道中沉降的数值研究

采用格子Boltzmann方法，数值模拟了考虑相互碰撞的两圆粒子的沉降，分析了Re数、初始相对位移及通道宽度对粒子沉降的影响．结果表明，在0.1＜Re＜20范围内， 粒子沉降具有周期性．Re数越大，两圆粒子的相互作用越强，粒子横向位移的幅度也越大．在大Re数时，沉降的过程是两个粒子交替领先；在较小Re数时，当后面的粒子接近的时候，领先的粒子被向右侧推了一段后仍会继续领先；对中等Re数，原先在后面的粒子在第一次加速后将取得领先位置并一直保持下去．粒子的初始分布位置对沉降的形态影响不大．管道宽度变化时，粒子总的沉降特性不变，而周期改变，管道越宽，周期越长．

Simulation of the Sedimentation of Two Circular Particles With Collision Considered in a Vertical Channel

D2Q9 model of Lattice Boltzmann equation method was used to simulate the sedimentation of two circular particles in a bounded two dimension channel. The characteristics of the sedimentation shows some periodicity for the Reynolds number Re chosen, 0.1~20. The larger the Reynolds number, the stronger the interaction between the two particles and the larger the transversal displacements. For large Re, the two particles leading alternately; for small Re, the initially leading particle will keep its leading position and for moderate Re, the initially upper particle will get leading position and keep it. The influence of the initially relative position of the two particles on sedimentation is small. The width of the channel won't change the characteristics of the sedimentation as a whole, but will change the period of the sedimentation. The wider the channel, the longer the period will be.