关键词:

颗粒碰撞, 硬球模型, 直接数值模拟, 稀疏气固两相流

Abstract:

To study the inter-particle collision behavior and its effects on particle dispersion in the dilute gas-solid flows, a three-dimensional two-phase turbulent jet was investigated by direct numerical simulation (DNS).A finite volume method and a fractional-step projection algorithm were used to solve the governing equations of gas phase and a Lagrangian method was used to trace the particles.A deterministic hard-sphere model was used to simulate inter-particle collision.It was found that inter-particle collision occurred frequently in the local regions with a higher particle concentration.The variation of average inter-particle collision number with Stokes number was not simple linear under the influence of local accumulation and turbulent transport effects.At St=0.1, average inter-particle collision number reached a peak value.Furthermore, particle distribution was more uniform when considering the effect of inter-particle collision, and the dispersion of the particles also increased in the lateral and spanwise directions.

Key words:

颗粒碰撞, 硬球模型, 直接数值模拟, 稀疏气固两相流