90°细弯管内稀疏气固两相流动数值研究

为了研究细弯管内稀疏气固流动条件下颗粒的分布特性，采用离散相模型( DPM)追踪颗粒行为，利用雷诺应力 模型( RSM)模拟气相的湍流流动，考虑了流体一颗粒间的双向耦合作用。通过对颗粒和气体流动行为的分析，得到了气 体压力、速度及颗粒浓度等的分布，研究了细弯管内颗粒流动行为的形成机理。结果表明：细弯管内气相压力沿流动方 向逐渐降低；弯管段内气相最大速度沿管外壁分布；水平段颗粒作下沉运动，弯管段颗粒浓度先分两束，后成单束贴壁流 动，最终杂乱分束，在竖直段彻底弥散化，这是由于各管段不同主要作用力所导致。

Numerical Study of Discrete Gas-Solid Two-Phase Flow in 900 Thin Elbows

In order to study flow regularity of discrete gas-solid flow in thin elbows. Discrete Particle Model ( DPM) and Reynolds Stress Model ( RSM) were used respectively to describe the gas and solid phase. and the two-way coupling of gas-solid phase was also considered. In present study, the flow behavior of particles and gas was analyzed, the distribution of gas pressure, velocity and particle concentration was obtained. and formation mechanism of particle behavior was also studied. The results indicated that the gas pressure gradually reduced along flow direction. The gas maximum velocity was distributed along outer wall of bended section. Above all, particles firstly sunk in horizontal section. formed separate beams at the beginning of bended section . then flow into a single beam along the outer wall and then split in several random beams, finally uniformly distributed in vertical section . which was caused by different forces in different sections.