三维矩形槽道中颗粒沉降的数值模拟

采用三维格子Boltzmann方法对矩形通道中的颗粒沉降进行了模拟研究．单颗粒沉降的模拟结果表明，颗粒最终的稳定沉降位置沿槽道中心线，不受颗粒初始位置和直径的影响．颗粒和壁面之间的两体相互效应可以用无因次沉降速度定量描述，无因次沉降速度的模拟结果和实验结果定量上吻合一致．模拟分析了双颗粒沉降的DKT（drafting, kissing and tumbling）过程，探讨了颗粒直径比以及壁面效应对DKT过程的影响．模拟发现当颗粒直径相同时，双颗粒的沉降过程为周期性的DKT过程，从而形成双螺旋形式的沉降轨迹，此螺旋沉降轨迹的频率和振幅受颗粒初始位置影响．从模拟结果中还得到颗粒群的最终稳定构型，并进行了构型对比分析．最后对包含49个颗粒的颗粒群沉降行为进行了模拟，说明多体相互作用在对称性的情况下可以简化．

Numerical Simulation of Particle Sedimentation in a 3D Rectangular Channel

The 3D lattice Boltzmann method was used to simulate the particle sedimentation in a rectangular channel.The results of single particle sedimentation indicated that the last position of particle was along the center line of the channel,regardless of the initial position and the particle diameter,so as to the particle Reynolds number.The wall effect on the terminal velocity was in good agreement with experimental results quantitatively.The drafting,kissing and tumbling(DKT) process was reproduced and analyze...