气固两相混合层二维涡配对的数值研究

采用双向耦合模型中的速度耦合模型，数值模拟了气固两相混合层中涡的配对、合并过程，文中采用拟谱方法对流场进行了直接数值模拟，用Lagrange模型跟踪固粒，结果发现，在双向耦合过程中Stokes数仍然是重要的参数，但不是唯一影响流场的参数，流场的发展还与固粒的体积浓度、固粒的相对密度以及固粒大小等因素有关。固粒抑制流场的发展，阻碍涡的配对、合并，加快了涡量的扩散；小St数的固粒仍然跟随流体运动，大St数的固粒趋向于低涡量区的趋势减弱。

Numerical Simulation on Vortex Pairing and Particles Dispersion in Two-dimensional Gas-solid Mixing Layer

The interactions between the vortex and the particles in Two-dimensional gas-solid mixing layer are investigated with two-way coupling model on the assumption that the flow around each particle is quasi-steady Stokesian locally and the average particle fraction is very low so that the interactions of the particles can be neglected. The spectral method is adopted to solve the Navier-stokes equation and each particle is traced with Lagrange method. The results indicate that the Stokes number is still an important parameter but not the only one in particle load flow if the fluid-particle interaction is considered, the particle fraction, relative density and size also act important roles. Particles impede the vortex pairing and the development of the flow. The dispersion of particles is similar to the results of one-way coupling model, but the centrifugal tendency of relative large Stokes number particle is delayed and weaken.