摘要
利用计算流体动力学软件FLUENT对旋风分离器内气固两相流动特性进行三维数值模拟,模拟气相流场采用雷诺应力模型,应用随机轨道模型模拟湍流流场中颗粒的运动轨迹,同时给出了不同抽气率下旋风分离器的速度、压力分布,计算出旋风器分级效率,模拟结果与文献实验数据吻合较好.结果表明,灰斗抽气可以提高锥体内旋转气流切向速度,轴向速度减少能够降低气流携带颗粒返混能力,并减小排气芯管下口短路流,提高旋风分离器分离效率.对于给定的旋风分离器,抽气率应有一最优值.
By utilizing stochastic tracking model, the moving track of particles in turbulence field was simulated, whilst the velocity and pressure distribution of cyclone separator under various blowdown rates were provided, and then the separating efficiency was computed. The simulation result matched the data from literatures quite well. The result indicates that the blowdown can increase the tangential velocity of whirling gas flow in conical section of cyclone and meanwhile the decrease of axial velocity helps to prevent the particle back mixing from gas flow, and decreases the short cut flow at the bottom of vortex finder. For a given cyclone separator,there is a corresponding optimal blowdown rate.
出处
《工程设计学报》
CSCD
北大核心
2008年第5期313-318,共6页
Chinese Journal of Engineering Design
关键词
旋风分离器
抽气率
分离性能
数值模拟
cyclone separator
blowdown rate
separation performance
numerical simulation
