孟亚丽 王 博

(兰州大学资源环境学院甘肃省环境污染预警与控制重点实验室,甘肃省兰州市,730000)



不同安装角重介旋流器内流场的数值模拟

孟亚丽 王 博

(兰州大学资源环境学院甘肃省环境污染预警与控制重点实验室,甘肃省兰州市,730000)

摘 要运用了计算流体力学(CFD)的方法,采用混合多相流模型(Mixture)结合雷诺应力模型(RSM)用来描述旋流器内介质的流动以及空气柱的变化,用拉格朗日颗粒追踪模型(LPT)来模拟颗粒的流动状态。在之前研究的基础上,对直径为1000 mm的重介质旋流器(DMC),通过改变其安装角度(－60°～90°)进行气－液－固的多相流动模拟,并分析不同安装角度对重介质旋流器内流场的影响。研究结果表明,安装角度的不同会影响重介质旋流器的分离性能,当安装角度从－60°增加到90°时,操作压力显著减小,密度偏差和溢流分流比都显著增加,通过流场分析得出在安装角度为10°左右时,流场稳定且DMC分选效果更佳。

关键词重介质旋流器 计算流体力学 多相流模拟 安装角度

Numerical simulation of flow field in dense-medium cyclone with different installation angles

Meng Yali,Wang Bo
(Gansu Key Laboratory for Environmental Pollution Prediction and Control,College of Earth and Environmental Sciences,Lanzhou University,Lanzhou,Gansu 730000,China)

Abstract By using the method of computational fluid dynamics(CFD)and adopting mixed multiphase flow model(Mixture)and Reynolds stress model(RSM),medium flow and air column changes in cyclone separator were described,flow condition of particles was simulated by Lagrangian particle tracking model(LPT).On the basis of previous research and by changing the installation angle(from－60°to 90°),gas-liquid-solid multiphase flow in the dense-medium cyclone(DMC)with a diameter of 1000 mm was simulated,and then the effects of the installation angles on the flow field of DMC were analyzed.The results showed that the different installation angles made differences in the separating performances of DMC.When the installation angle increased from－60°to 90°,operating pressure significantly decreased,density deviation and overflow split ratio both increased.It had been found by analyzing the flow field that,when the installation angle was 10°,the flow field was stable and the separating effect was better.

Key words dense-medium cyclone,computational fluid dynamic(CFD),multiphase flow simulation,installation angle

目前重介质旋流器(DMC)在国内应用广泛,主要是由于其结构简单、单位处理量大、分选效率高以及适合处理难选煤或极难选煤.尽管重介质旋流器结构简单,但其内部具有复杂的多相流场,包括气体、液体、煤颗粒以及大小密度各异的磁铁矿颗粒和非磁铁矿颗粒的流动等.近年来,运用计算流体动力学方法(CFD)已经成为研究旋流器流场的重要手段.相关专家使用CFD软件FLUENT来模拟水力旋流器中流体……