论文部分内容阅读
Direct numerical simulation(DNS)of gas-solid flow at high resolution has been carried out by coupling the lat-tice Boltzmann method(LBM)for gas flow and the discrete element method(DEM)for solid particles.However,the body force periodic boundary condition(FPBC)commonly used to cut down the huge computational cost of such simulation has faced accuracy concs.In this study,a novel two-region periodic boundary condition(TPBC)is presented to remedy this problem,with the flow driven in the region with body force and freely evolv-ing in the other region.With simulation cases for simple circulating fluidized bed risers,the validity and advan-tages of TPBC are demonstrated with more reasonable heterogeneity of the particle distribution as compared to the corresponding case with FPBC.