防返混锥对旋风分离器流场影响的大涡模拟  

Large eddy simulation forEffect of Anti-backmixingCone on Flow Field inCyclone Separator

作　　者：龙薪羽 刘根凡[2] 谢翔[2] Long Xinyu;Liu Genfan;Xie Xiang(SUNNY Technologies Incorporation Ltd,Huangshi 435003,China;School of Energy and Power Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]黄石山力科技股份有限公司,湖北黄石435003 [2]华中科技大学能源与动力工程学院,武汉430074

出　　处：《化工设备与管道》2019年第1期20-25,共6页Process Equipment & Piping

基　　金：煤燃烧国家重点实验室开放基金资助项目(FSKLCC1207)

摘　　要：防返混锥可用于常规旋风分离器的改造以提升分离性能。基于大涡模拟(LES),从平均流场、湍流脉动和流场稳定性等方面,系统地研究了配置防返混锥后旋风分离器全局流场的变化情况。具体结论如下:圆筒段和圆锥段的平均切向速度略有提升、中心平均轴向速度轻微上移,灰斗壁面附近的切向速度几乎不变、轴向速度有所提升,灰斗底部中心区域的切向速度和轴向速度均明显降低;防返混锥附近切向与轴向的湍流脉动轴对称性有所恶化,且局部位置脉动数值增幅较大,但灰斗底部区域的脉动得以削弱;尽管在临近防返混锥的区域内旋进涡核(PVC)摆动有所增强,但全局流域的涡核平均偏心距仍降低了近21.3%。The anti-backmixing cone can be used for the reforming of the conventional cyclone separators to improve the separation performance. Based on large eddy simulation(LES), in this paper the changes of the global flow field in a cyclone separator after being equipped with an anti-backmixing cone, in terms of average flow profiles, velocity fluctuations and stability of flow field,were systematically studied. The concrete conclusions were as follows: the average tangential velocity of the cylinder and conical section slightly increased, the average axial velocity nearby the centerline moved upward to a small extent.The tangential velocity near the dust hopper wall remained unaffected, but the axial velocity of these regions increased. The tangential and axial velocity in the center area at the bottom of the dust hopper decreased dramatically. The axis symmetry of tangential and axial velocity fluctuations in the vicinity of the anti-backmixing cone deteriorated, meanwhile, the velocity fluctuations valve increased apparently in local region. However, the velocity fluctuations in the bottom of the dust hopper were weakened. Although in the area adjacent to the anti-backmixing cone where the swinging of processing vortex core(PVC) was enhanced, in the global flow fields where the mean eccentricity of PVC was still reduced by nearly 21.3%.

关 键 词：旋风分离器 防返混锥 大涡模拟 旋进涡核 

分 类 号：TQ051.8[化学工程] TH122[机械工程—机械设计及理论]