高温旋风分离器流场的特性研究和数值模拟
摘要
高温旋风分离器是循环流化床锅炉分离机构的重要组成部分,由于其结构简单,分离效率高,广泛运用于循环流化床锅炉中。为了掌握高温旋风分离器内部流场特性,本文以计算流体力学软件Fluent6.3为基础,景德镇电厂150WM循环流化床锅炉高温旋风分离器为研究对象,对其内部流场进行模拟和分析。
通过本文的研究,首先确定一套适合高温旋风分离器内部流场计算的数值方法,在这基础上,对高温旋风分离器气相流场进行了模拟研究,其中包括速度场、压力场以及湍流结构的分析。其次对高温旋风分离器两相流场进行了研究,包括气固两相流模型,颗粒运动轨迹、颗粒浓度场的分布、分离效率的研究等内容。最后提出了一种新型弧形入口型的高温旋风分离器。
(1)在对旋风分离器内部流场进行数值模拟时,湍流模型采用雷诺应力模型、对流项采用QUICK格式进行离散、对于控制方程组采用SIMPLEC算法求解、采用分区组合来划分网格。
(2)从模拟中可以清楚看出,总体上高温旋风分离器内部流场由两层涡流组成。在入口区,可以看到气流紊乱,对壁面造成严重的冲刷。在旋风筒区域流场的对称性较好,而在锥体部分,流场的对称性较差。
(3)本文提出一种弧形入口型高温旋风分离器,并对其流场进行模拟。这种结构使得入口流场较为稳定,减少了对壁面的冲刷,内部流场的对称性要好于原型,同时分离效率有了一定的提高。
High temperature cyclone separator with simple structure and high separation efficiency is an important part of CFBB with separation equipment ,which has been widely used in CFBB. By using the computational fluid dynamics software FLUENT6.3, the internal flow in high temperature cyclone separator of Jingdezhen Power 150MW CFBB is simulated and analyzed to understand the flow characteristics in separator.
Through researching this thesis, the method of numerical for computing the internal flow in high temperature cyclone separator will been confirmed at first, the gas flow in cyclone separator is simulated afterwards, including velocity field, pressure field and analysis of turbulence structure, two-phase flow is researched, which includes gas-solid two-phase flow model, paths of particles , particles concentration field distributions and so on. A new high temperature cyclone separator with arc way is presented in the end.
(1) The internal flow in cyclone separator is simulated by RSM model for turbulent flow, QUICK format for different scheme, SIMPLEC for controlling equations, zoning combination of grid.
(2) The internal flow in high temperature cyclone separator is double vortex on the whole flow from simulating. In the entrance area, the gas flow is disordered and wall is strong erosion and the flow is symmetrical in cyclone tube area, however, the flow is dissymmetrical in cone area.
(3) The flow is simulated for arc way high temperature cyclone separator , the flow in entrance area is stability and erosion of wall is mitigated, symmetrical in internal flow is better than original model, and separation efficiency is enhanced.
通过本文的研究,首先确定一套适合高温旋风分离器内部流场计算的数值方法,在这基础上,对高温旋风分离器气相流场进行了模拟研究,其中包括速度场、压力场以及湍流结构的分析。其次对高温旋风分离器两相流场进行了研究,包括气固两相流模型,颗粒运动轨迹、颗粒浓度场的分布、分离效率的研究等内容。最后提出了一种新型弧形入口型的高温旋风分离器。
(1)在对旋风分离器内部流场进行数值模拟时,湍流模型采用雷诺应力模型、对流项采用QUICK格式进行离散、对于控制方程组采用SIMPLEC算法求解、采用分区组合来划分网格。
(2)从模拟中可以清楚看出,总体上高温旋风分离器内部流场由两层涡流组成。在入口区,可以看到气流紊乱,对壁面造成严重的冲刷。在旋风筒区域流场的对称性较好,而在锥体部分,流场的对称性较差。
(3)本文提出一种弧形入口型高温旋风分离器,并对其流场进行模拟。这种结构使得入口流场较为稳定,减少了对壁面的冲刷,内部流场的对称性要好于原型,同时分离效率有了一定的提高。
High temperature cyclone separator with simple structure and high separation efficiency is an important part of CFBB with separation equipment ,which has been widely used in CFBB. By using the computational fluid dynamics software FLUENT6.3, the internal flow in high temperature cyclone separator of Jingdezhen Power 150MW CFBB is simulated and analyzed to understand the flow characteristics in separator.
Through researching this thesis, the method of numerical for computing the internal flow in high temperature cyclone separator will been confirmed at first, the gas flow in cyclone separator is simulated afterwards, including velocity field, pressure field and analysis of turbulence structure, two-phase flow is researched, which includes gas-solid two-phase flow model, paths of particles , particles concentration field distributions and so on. A new high temperature cyclone separator with arc way is presented in the end.
(1) The internal flow in cyclone separator is simulated by RSM model for turbulent flow, QUICK format for different scheme, SIMPLEC for controlling equations, zoning combination of grid.
(2) The internal flow in high temperature cyclone separator is double vortex on the whole flow from simulating. In the entrance area, the gas flow is disordered and wall is strong erosion and the flow is symmetrical in cyclone tube area, however, the flow is dissymmetrical in cone area.
(3) The flow is simulated for arc way high temperature cyclone separator , the flow in entrance area is stability and erosion of wall is mitigated, symmetrical in internal flow is better than original model, and separation efficiency is enhanced.
引文
[1]党黎军.循环流化床锅炉的启动调试与安全运行.北京:中国电力出版社.2002:1.
[2]岑可法,倪明江等.循环流化床锅炉理论设计与运行.北京:中国电力出版社.1997:10-11,494,497-498,513-517.
[3]上海锅炉厂有限公司.1×150MW循环流化床锅炉技术培训指导手册.上海:上海锅炉厂有限公司.2003:20-21.
[4]陈克俭.循环流化床锅炉旋风分离器效率的计算.动力工程.2003.23(2):2346-2349.
[5]陈绍明,吴光兴等.除尘技术的基本理论与应用.北京:中国建筑工业出版社.1981.
[6]Rosin P,Rammler E and Intelmann W.Grundlagen and Grenzen der Zyklonentsaubung.Z,Ver.Dtsch.Ing.1932,76(16):433.
[7]J.C.Gwozdz,ctl.Fluidized Bed Combustion Moves into Vtility Appli cations.1986.
[8]王浩.旋风分离器内两相流场的数值模拟研究[硕士论文].兰州:兰州理工大学.2007.
[9]White J A.Elliptic Grid Generation with Orthogonally and Spacing Control on an Arbitrary Number of Boundaries.A MA Press:1990,90-1568
[10][日]井伊谷刚一.马文彦译.除尘装置的性能.北京:机械工业出版社.1981.
[11]Sproull W T.Air Pollution and Its Control.New York Exposition Press:1970.
[12]周韬.旋风分离器的气固两相特性研究与数值模拟[硕士论文].上海:上海交通大学.2007.
[13]Dietz P W.Collection efficiency of cyclone separator[J].AICHE.1981,27:888-892.
[14]Boysan F,Ayers W H and Swithenbank J.A Fundamental Mathematical Modeling[J].TransIchem E.1982,60:222-230.
[15]Salcedo R.L.Collection efficiency and particle-size distribution from sampling cyclones-comparison of recent theories with experimental data[J].Engineering.1993,71:20-25.
[16]向晓东.计算旋风器分离器效率的一种新方法.通风除尘.1990 (2):1—7,47.
[17]张吉光,叶龙.高效旋风器分级效率理论计算的新方法.青岛建筑工程学院学报.1991.12(4):41—48.
[18]Abdually A F,et al.Operating Experience of a Circulating Fluidized bed Boiler Designed by Foster Wheeler.In:Marx w B(ed).Proc.of Fifth Annual Fluidized Bed conference.California:Cibo,1989,19.
[19]Robert Gamble,et al.Pyroflow compact:A Second Generation CFB Boiler by Ahlstrom pyropower.Rubow L N(ed).Proc.Of 13th Inter.Conf.on FBC.San Diego.ASME Press:1993,751.
[20]Ruotta S,ea al.Development of a CFB Reactor with a Horizontal Cyclone.Mustonen J P(ed).Proc.Of 9th Int.Conf.on FBC.Bost on:ASME Press:1987.Vol.2:824.
[21]Belin F.CFB Boilers with an Impact Particle Separator Design and Operating Exerience.In:Avidan A A(ed).Proc.Of 4~(th) Int.Conf.on CFB.Pennsylvania.1993,233-238.
[22]化学工程手册编委会.化学工程手册.Vol.5.北京:化学工业出版社.1989.
[23]陶文铨.数值传热学.第2版.西安:西安交通大学出版社.2001:333-335,397,198.
[24]郭烈锦.两相与多相流动力学.西安:西安交通大学出版社.2002:592.
[25]王福军.计算流体动力学分析--CFD软件原理与应用.北京:清华大学出版社.2004:117,44.
[26]李长志,王莹,董鹏.湍流气固两相流动数值模拟理论研究的最新进展.电站系统工程.2002.18(3):19-20.
[27]Crowe C J.The state-of-the-air in the development of numerical m odels for dispersed flows,Proc.Int.[J].Multiphase Flows.91 Tsuku ba,1991,3:49-60.
[28]W.P.Jones and B.C.Launder.The Prediction of Lamininarization with a Two-equation Model of Turbulence.Int.[J].Heat and mass Transfer,1972,Vol.15:301-314.
[29]V.Yakhot,S.A.Orzag,Renormalization group analysis of turbulence.Basic theory[J].Scient Comput.1986.1:3-11.
[30]费祥麟.高等流体力学.西安:西安交通大学出版社.1989.
[31]Song Fu.Modelling of the strongly swirling flows with second-moment closures[J].The Recent Developments In Turbulence Research,Tsinghua University,1994,22-41.
[32]Hong S and Leschziner M A.Computation of highly swirling confi ned flow with a Reynolds stress turbulence model[J].AIAAJ.1989,27(1):57-63.
[33]A J Hoekstra,J J Derksen and H E A Van DenAkker.An experimental and numerical study of turbulent swirling flow in gas cyclones.Chemical Engineering Science Press:1999,54.
[34]F Byson,J Swithenbank and W Hayers.Mathematical modeling of gas-flows in cyclone separators.TransIchem E.1982.
[35]王海刚,刘石.不同湍流模型在旋风分离器三维数值模拟中的应用和比较.热能动力工程.2003.18(4):337-342.
[36]HSIEH KT,RAJAMANI R K,Mathematical model of the hydrocyc one based on physics of fluid flow[J].AIChE Journal.1991,37(5):735-746.
[37]MALHOTRA A,BRANION R M R,HAUPTMANN E G.Modeling the flow in a hydrocyclone[J].The Canadian Journal of Chemical Engineering.1994,72:953-960.
[38]Phyfe NM.CFD modeling of cyclone separator.Fluent Users Group Meeting.Danvers,Massachussetts,1999.
[39]S.V.Patanker,D.B.Spalding,A calculation processure for heat,mass and momentum transfer in three-dimensional parabolic flows[J].Hea t Mass Transfer.1972,15:1787-1806.
[40]J.P.Van Doormal,G.G.Raithby,Enhancement of the SIMPLE method for predicting incompressible fluid flows[J].Numerical Heat Transf er.1984,7:147-163.
[41]张海红.旋风分离器流场与分离性能的数值模拟研究[硕士论文].郑州:郑州大学.2004.
[42]苏虎.循环流化床锅炉旋风分离器内部气固两相流动的数值模拟[硕士论文].西安:西安交通大学.2004.
[43]祝传钰.内部结构变形对旋风分离器性能影响的数值仿真研究[硕士论文].大连:大连理工大学.2006.
[44]韩占忠,王敬,兰小平.Fluent流体工程仿真计算实例与应用.北京:北京理工大学出版社.2004.
[45]S V Patankar.Numerical Heat Transfer and Fluid Flow.Hemisphere,Washington.D.C.1980.
[46]Casal,J,and Martinez,J.M.Calculating pressure drop in cyclones.2~(nd) Congr.Mediterr.Ingenieria Quimica,Barcelona,November,1981.
[47]Stairrnand C J.Pressure Drop in Cyclone Separators Enginerring[J].Cyclone Enginerring.1949:168.
[48]First M W.Cyclone dust Collector Design.Am.Soc.Mech.Eng.1949:49-127.
[49]Shepherd C B and Lapple C E.Flow Pattern and Pressure Drop in cyclone Dust Collectors.Cyclone Without Inlet Vane.Ind.Eng.Ch em.,1940:32.
[50]时钧,汪家鼎,余国宗等.化学工业手册.北京:化学工业出版社.1996:2.
[51]王绍亭,陈涛.化工传递过程基础.北京:化学工业出版社.1998.
[52]王海刚.旋风分离器中气-固两相流数值计算与实验研究[博士论文].北京:中国科学院.2003.
[53]张锐.粗煤粉分离器的三维气固两相流动研究[博士论文].吉林:吉林大学.2004.
[54]周力行.湍流两相流动与燃烧的数值模拟.北京:清华大社.1991:135-136
[55]姚玉英.化工原理.天津:天津大学出版社.1999.153.
[2]岑可法,倪明江等.循环流化床锅炉理论设计与运行.北京:中国电力出版社.1997:10-11,494,497-498,513-517.
[3]上海锅炉厂有限公司.1×150MW循环流化床锅炉技术培训指导手册.上海:上海锅炉厂有限公司.2003:20-21.
[4]陈克俭.循环流化床锅炉旋风分离器效率的计算.动力工程.2003.23(2):2346-2349.
[5]陈绍明,吴光兴等.除尘技术的基本理论与应用.北京:中国建筑工业出版社.1981.
[6]Rosin P,Rammler E and Intelmann W.Grundlagen and Grenzen der Zyklonentsaubung.Z,Ver.Dtsch.Ing.1932,76(16):433.
[7]J.C.Gwozdz,ctl.Fluidized Bed Combustion Moves into Vtility Appli cations.1986.
[8]王浩.旋风分离器内两相流场的数值模拟研究[硕士论文].兰州:兰州理工大学.2007.
[9]White J A.Elliptic Grid Generation with Orthogonally and Spacing Control on an Arbitrary Number of Boundaries.A MA Press:1990,90-1568
[10][日]井伊谷刚一.马文彦译.除尘装置的性能.北京:机械工业出版社.1981.
[11]Sproull W T.Air Pollution and Its Control.New York Exposition Press:1970.
[12]周韬.旋风分离器的气固两相特性研究与数值模拟[硕士论文].上海:上海交通大学.2007.
[13]Dietz P W.Collection efficiency of cyclone separator[J].AICHE.1981,27:888-892.
[14]Boysan F,Ayers W H and Swithenbank J.A Fundamental Mathematical Modeling[J].TransIchem E.1982,60:222-230.
[15]Salcedo R.L.Collection efficiency and particle-size distribution from sampling cyclones-comparison of recent theories with experimental data[J].Engineering.1993,71:20-25.
[16]向晓东.计算旋风器分离器效率的一种新方法.通风除尘.1990 (2):1—7,47.
[17]张吉光,叶龙.高效旋风器分级效率理论计算的新方法.青岛建筑工程学院学报.1991.12(4):41—48.
[18]Abdually A F,et al.Operating Experience of a Circulating Fluidized bed Boiler Designed by Foster Wheeler.In:Marx w B(ed).Proc.of Fifth Annual Fluidized Bed conference.California:Cibo,1989,19.
[19]Robert Gamble,et al.Pyroflow compact:A Second Generation CFB Boiler by Ahlstrom pyropower.Rubow L N(ed).Proc.Of 13th Inter.Conf.on FBC.San Diego.ASME Press:1993,751.
[20]Ruotta S,ea al.Development of a CFB Reactor with a Horizontal Cyclone.Mustonen J P(ed).Proc.Of 9th Int.Conf.on FBC.Bost on:ASME Press:1987.Vol.2:824.
[21]Belin F.CFB Boilers with an Impact Particle Separator Design and Operating Exerience.In:Avidan A A(ed).Proc.Of 4~(th) Int.Conf.on CFB.Pennsylvania.1993,233-238.
[22]化学工程手册编委会.化学工程手册.Vol.5.北京:化学工业出版社.1989.
[23]陶文铨.数值传热学.第2版.西安:西安交通大学出版社.2001:333-335,397,198.
[24]郭烈锦.两相与多相流动力学.西安:西安交通大学出版社.2002:592.
[25]王福军.计算流体动力学分析--CFD软件原理与应用.北京:清华大学出版社.2004:117,44.
[26]李长志,王莹,董鹏.湍流气固两相流动数值模拟理论研究的最新进展.电站系统工程.2002.18(3):19-20.
[27]Crowe C J.The state-of-the-air in the development of numerical m odels for dispersed flows,Proc.Int.[J].Multiphase Flows.91 Tsuku ba,1991,3:49-60.
[28]W.P.Jones and B.C.Launder.The Prediction of Lamininarization with a Two-equation Model of Turbulence.Int.[J].Heat and mass Transfer,1972,Vol.15:301-314.
[29]V.Yakhot,S.A.Orzag,Renormalization group analysis of turbulence.Basic theory[J].Scient Comput.1986.1:3-11.
[30]费祥麟.高等流体力学.西安:西安交通大学出版社.1989.
[31]Song Fu.Modelling of the strongly swirling flows with second-moment closures[J].The Recent Developments In Turbulence Research,Tsinghua University,1994,22-41.
[32]Hong S and Leschziner M A.Computation of highly swirling confi ned flow with a Reynolds stress turbulence model[J].AIAAJ.1989,27(1):57-63.
[33]A J Hoekstra,J J Derksen and H E A Van DenAkker.An experimental and numerical study of turbulent swirling flow in gas cyclones.Chemical Engineering Science Press:1999,54.
[34]F Byson,J Swithenbank and W Hayers.Mathematical modeling of gas-flows in cyclone separators.TransIchem E.1982.
[35]王海刚,刘石.不同湍流模型在旋风分离器三维数值模拟中的应用和比较.热能动力工程.2003.18(4):337-342.
[36]HSIEH KT,RAJAMANI R K,Mathematical model of the hydrocyc one based on physics of fluid flow[J].AIChE Journal.1991,37(5):735-746.
[37]MALHOTRA A,BRANION R M R,HAUPTMANN E G.Modeling the flow in a hydrocyclone[J].The Canadian Journal of Chemical Engineering.1994,72:953-960.
[38]Phyfe NM.CFD modeling of cyclone separator.Fluent Users Group Meeting.Danvers,Massachussetts,1999.
[39]S.V.Patanker,D.B.Spalding,A calculation processure for heat,mass and momentum transfer in three-dimensional parabolic flows[J].Hea t Mass Transfer.1972,15:1787-1806.
[40]J.P.Van Doormal,G.G.Raithby,Enhancement of the SIMPLE method for predicting incompressible fluid flows[J].Numerical Heat Transf er.1984,7:147-163.
[41]张海红.旋风分离器流场与分离性能的数值模拟研究[硕士论文].郑州:郑州大学.2004.
[42]苏虎.循环流化床锅炉旋风分离器内部气固两相流动的数值模拟[硕士论文].西安:西安交通大学.2004.
[43]祝传钰.内部结构变形对旋风分离器性能影响的数值仿真研究[硕士论文].大连:大连理工大学.2006.
[44]韩占忠,王敬,兰小平.Fluent流体工程仿真计算实例与应用.北京:北京理工大学出版社.2004.
[45]S V Patankar.Numerical Heat Transfer and Fluid Flow.Hemisphere,Washington.D.C.1980.
[46]Casal,J,and Martinez,J.M.Calculating pressure drop in cyclones.2~(nd) Congr.Mediterr.Ingenieria Quimica,Barcelona,November,1981.
[47]Stairrnand C J.Pressure Drop in Cyclone Separators Enginerring[J].Cyclone Enginerring.1949:168.
[48]First M W.Cyclone dust Collector Design.Am.Soc.Mech.Eng.1949:49-127.
[49]Shepherd C B and Lapple C E.Flow Pattern and Pressure Drop in cyclone Dust Collectors.Cyclone Without Inlet Vane.Ind.Eng.Ch em.,1940:32.
[50]时钧,汪家鼎,余国宗等.化学工业手册.北京:化学工业出版社.1996:2.
[51]王绍亭,陈涛.化工传递过程基础.北京:化学工业出版社.1998.
[52]王海刚.旋风分离器中气-固两相流数值计算与实验研究[博士论文].北京:中国科学院.2003.
[53]张锐.粗煤粉分离器的三维气固两相流动研究[博士论文].吉林:吉林大学.2004.
[54]周力行.湍流两相流动与燃烧的数值模拟.北京:清华大社.1991:135-136
[55]姚玉英.化工原理.天津:天津大学出版社.1999.153.