Numerical Simulation of Three Dimensional Gas-Particle Flow in a Spiral Cyclone
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摘要: 对螺旋型旋风分离器进行了两相流场的三维数值模拟.气体流场通过求解三维N-S方程得到,湍流模型采用了雷诺应力模型.计算结果表明,旋风分离器内部的流场分为两部分:螺旋通道内比较稳定的流场和筒体中心区域的复合涡结构流场.对颗粒运动轨迹的计算表明,颗粒在入口处的初始位置对颗粒分离有比较显著的影响.同时得到了不同入口速度下颗粒的分级效率曲线,并给出了气体流量对旋风分离器性能的影响,结果显示:气体流量的增加会提高分离效率,但同时导致压力损失的急剧增加.Abstract: The three-dimension gas-particle flow in a spiral cyclone is simulated numerically. The gas flow field was obtained by solving the three-dimension Navier-Stokes equations with Reynolds stress model (RSM). It is shown that there are two regions in the cyclone, the steadily tangential flow in the spiral channel and the combined vortex flow in the centre. Numerical results for particles trajectories show that the initial position of the particle at the inlet plane substantially affects its trajectory in the cyclone. The particle collection efficiency curves at different inlet velocities were obtained and the effects of inlet flow rate on the performance of the spiral cyclone were presented. Numerical results also show that the increase of flow rate leads to the increase of particles collection efficiency, but the pressure drop increases sharply.
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Key words:
- spiral cyclone /
- numerical simulation /
- particle trajectory /
- collection efficiency
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