摘要
各种热电、核电厂排出的热污(废)水在直接进入环境流体之前,以孔口浮射流的形式释放污水并确保污水在排污口快速混合非常重要。因此,精确的了解和预测浮射流的特性与混合状况有很重要的意义,而用数值模拟的方法来全面研究环境流体中射流的混合过程则是一个重要的技术手段。
在回顾射流的理论,并对目前的各种紊流数值方法进行了讨论分析的基础上,本文有针对性的研究了在同向流动环境中使用多孔扩散器进行热废水排放的情况,对其近区的流场和温度场特性进行了数值模拟,分别利用FLUENT软件中的RNGκ-ε模型和雷诺应力RMS紊流模型,并用有限体积法和SIMPLE法进行模型方程的求解,得到了不同流速比和不同射流温度下的流场和温度场;浮射流的轨迹线;轴线上温度和速度的衰减规律;浮力对射流轨迹线的影响,并对多孔热水浮射流中对流态具有重要影响的流速比和孔间间距进行了探讨,分别计算了不同流速比情况下的不同孔间间距的流速分布和温度分布,得到了一些很有价值的射流规律和结论。
本文利用多种数学模型对复杂的三维流场进行了数值模拟,为课题后期的实验研究提供了参考对照的依据,对研究各种热、核电厂热污(废)水排入环境水体有一定的实用价值,并能为冷却水工程提供理论分析依据。最后对所做的工作和成果进行了总结,指出了论文的不足,并对下一步的工作做出了展望。
Before the thermal wastewater of the thermal and nuclear power plants intrudes into the environmental water, it is important to ensure that high initial mixing is achieved in the vicinity of the discharge structure by releasing the contaminated fluid through orifices and in the form of buoyant jets. Therefore, accurate understanding and predictions of the behaviour of a buoyant jet and its mixing characteristics are desired.
In this research, jet theories were reviewed different mathematical modeling technologies of turbulent flow were analyzed and valued, and then I took the numerical model research of the velocity and temperature distribution of near-field flow behavior when using diffusers to discharge waste water. In the mathematical model research, with the reference to software of FULENT,standard two equation k-εturbulent model、the Renormalization Groupk-ε(RNG k-ε)model and Reynolds Stress equation(RMS) model are adopted.At the same time,the model equations are solved in finite volume and SIMPLE methods. I have got the velocity and temperature field, buoyant jet trajectory, temperature attenuation along the axis, buoyant jet trajectory impacted by buoyancy force under different velocity ratio and different jet temperature. The velocity ratio and ports space, which have very important effect on flowing behavior in multiport thermal wastewater jet, were investigated and speed and temperature distribution were calculated under different ports space of various velocity ratio. And we can also get some jet laws and results.
In this parer,I use different models simulated the complicated 3D flow , it has a referred value for the later experimental study. It is valuable to study the regulars of thermal wastewater in the thermal and nuclear power plants intrude into the environmental water. It can alsoprovide some theoretic foundations for cooling water projects.At the last, all the work and fruits in the paper were summarized and the defects and further work were elaborated.
引文
[1]Fischer H B;etal.Mixing in inland and coastal waters[M].NEW York:Academic Press,1979,315-389
[2]李行伟著,陈鸣钊,张逢甲译,李耀中校.浮射流理论及其在环境中的应用[M].河海大学教务处,南京,1989
[3]余常昭,环境流体力学导论[M].北京:清华大学出版社,1992:135-190
[4]L.Pantzlaff,R.M.Lueptow,Transient positively and negatively buoyant turbulent round jets[J].Experiments in Fluids,1999,27(1):117-125
[5]Daniel Goldman and Yogesh Jaluria,Effect of opposing buoyancy on the flow in free and wall jets[J].Fluid Mech.,1986,166(1):41-56
[6]李炜,槐文信,浮力射流的理论及应用[M].1997,科学出版社
[7]左东启编著.模型试验的理论和方法[M].北京:水利电力出版社,1984.8
[8]顾佩龙等.长江口污水排放试验和计算的研究[J].水利水运科学研究,1987(1)
[9]顾佩龙.上海市合流污水治理一期工程排放口模型[J].水利水运科学研究,1987(2)
[10]严忠民,蒋传丰,周春天,刘明明.厦门市污水处理二厂排海管扩散器断面模型试验报告(水科912025)[R].河海大学水利水电科学研究所,1991.10
[11]严忠民,蒋传丰.海洋扩散器排放标准水力设计及模型试验[R].河海大学水利水电科学研究所,1990
[12]韦鹤平,徐亮.上海星火工业区污水排海工程排放管工程参数研究[R].上海,1989.11
[13]国家环保局,同济大学.上海市竹园排放口扩散管模型试验研究报告[R].上海,1991.4
[14]徐高田,韦鹤平.量纲分析对污水近区初始稀释度变化规律的探讨[J].上海环境科学,1997,16(10)
[15]徐高田.长江口白龙港水域污水稀释扩散规律研究[D].上海:同济大学,1996
[16]任佐皋,项菁.喷口装置的水力模型试验[J].造船工业建设,1992(1):51-52
[17]项菁,任佐皋.污水排江扩散器的水力模型试验[J].造船工业建设,1992(1):47-50
[18]陈永娟,吴宝武,李国平等.四堡污水处理厂排污管喷口研究[J].河海大学学报,1994,22(1):40-45
[19]蒋传丰,严忠民,周春天,刘明明.污水排海管扩散器模型试验研究[J].河海大学学报,1994,22(1):1-6
[20]左东启,严忠民,蒋传丰,唐洪武.大水域潜管排放试验研究(水科933005)[R].河海大学水利水电科学研究所.1993.3
[21]熊鳌魁,詹德新等.近水面淹没喷嘴射流流场特性的试验研究[J].水动力学研究与进展A辑,1995.10(4)
[22]Anthony,D.G.,and Willmarth,W.W.Turbulence measurements in a round jet beneath a free surface[J].Fluid Mech.,1992,Vol.243:6997-20
[23]Morton,Taylor and Turner.Turbulent gravitational convection from maintained and instantaneous sources[M].Proc.Roy.Soc A234:1-23
[24]List,H.B.,and Imberger,J.Turbulent entrainment in buoyant jets[J].Hydr.Div,ASCE,1973.Vol.99:1461-1474
[25][美]H.B费希尔等著.清华大学水力学教研组译.内陆及近海水域的混合[M].北京:水利电力出版社,1987
[26]槐文信.圆形卷流特性的研究[J].武汉水利电力学院学报,1992,25(2):113-118
[27]Papanicolaous,P.N.,and List,E.J.Investigation of round vertical turbulent buoyant jets[J].Fluid Mech.,1988,195(1):341-391
[28]Papanicolaous,P.N.,and List,E.J.Statistical and spectral proper lies of tracer concentration in round buoyant jets[J].Heat and Mass Transfer,130(1):2059-2071
[29]Rodi,W.Turbulent buoyant jet and plumes[M].Pergamon Press,Oxford,New York,1982
[30]Chen and Rodi,W.Vertical turbulent buoyant jets一A renewof experiment data[M].Pergamon Publisher,New York,1980
[31]Chiang H C,and Sill B L,ENTRAINMENT MODELS AND THEIR APPLICATION TO JETS IN A TURBULENT CROSS FLOW[J].Atrnospheric Environment,1985,19(9):1425-1438
[32]Lee J H W,and Cheung V,Generalized Lagrangian model for buoyant jets in current[J].Journal of Environmental Engineering,1990,116(6):1085-1106
[33]Wang H,and Law A W K,Second-order integral model for a round turbulent buoyant jet[J].Journal of Fluid Mechanics,2002(459):397-428
[34]Mukhtasor,Lye L M,and Sharp J J,A new approach to modeling initial dilution of a buoyancy-dominated jet in moving water[J].Journal of Environmental Engineering and Science,2002(1):101-111
[35]Hirst E A,Analysis of round turbulent buoyant jets discharged to flowing stratified ambient[M].Oak Ridge National Laboratory,1971
[36]槐文信,李炜,流动环境中倾斜浮力射流的积分方法[J].水科学进展,1993,4(4):301-308
[37]余常昭,李春华.圆形断面自由紊动水射流卷吸实验研究[J].气动实验与量测控制,1996(1)
[38]Fan,L.N.Turbulent buoyant jets into stratified or flowing ambient fluids[R].No.KH-R-18,Hydraulic and Water Resources,California Institute of Technology,1967
[39]Hirst,E.A.Analysis of round,turbulent,buoyant jets discharged to flowing stratified ambient.Oak Ride National Lab[R].ORNL-4683,1971
[40]Chiang,H.G,and Sill,B.L.Entrainment models and their application to jets in a turbulent cross flow[J].Atmospheric Environment,1985,19(1):1425-1438
[41]槐文信,李炜.静止环境中倾斜浮力射流[J].武汉水利电力学院学报,1991,24(5):489-494
[42]槐文信,李炜.流动环境中倾斜浮力射流的积分方法[J].水科学进展,1993,4(4)
[43]李炜,槐文信.平面射流和卷流的相似解[J].武汉水利电力学院学报,1992,25(3):219-228
[44]Paully,A.T.,et al.Similarity solution for plane and radial jets using a k-ε turbulence model[J].ASCE,J.of Ftuid Engineering,1985,Vol.107:78-85
[45]槐文信,李炜.圆形射流和卷流的相似解[J].应用数学和力学,1993,14(7)
[46]黄真理.平面激光诱导荧光(PLIF)技术及其测量射流浓度场的研究[D].北京:清华大学,1993
[47]陈朝泉.数字图像和PLIF技术研究潮流底部多孔射流浓度场及其分形[D].北京:清华大学,1997
[48]Chu,P C.K.Mixing of turbulent advected line puffs.Ph.D.Thesis[R].University of Hong Kong,Hong Kong,1996
[49]张兆顺,崔桂香编著,流体力学[M].清华大学出版社,2005:14-19
[50]Frick W E.Non-empirical closure of the plume equations[J].Atmospheric Environment,1984,18(4):653-662.
[51]Fan L N.Turbulent buoyant jets into stratified or flowing ambient fluids JR].W M Keck Laboratory of Hydraulics and Water Resources,California Institute of Technology.1967.Pasadena,USA
[52]Schatzmann M.An integral model of plume rise[J].Atmospheric Environment,1979,13(5):721-731.
[53]Chu V H,Lee J H W.General integral formulation of turbulent buoyant jets in cross flow[J].Journal of Hydraulic Engineering,1996,122(1):27-34.
[54]槐文信.同流热污水排放的三维数学模型及计算方法[J].武汉水利电力大学学报,1997,30(4)1-5
[55]袁银忠,黄细彬.岸边排放口近区流场和浓度场特性的分析[J].水利学报,1989(9)
[56]Partaker,S.V.,et al.Prediction of the 3-D velocity field of a deflected turbulent jet.Tran.ASME[J].Fluid Engng,1977:58-762
[57]Rodi,W.,and Srivata,S.K.A locally elliptic calculation procedure for 3-D flows and its application to a jet in cross-flow[J].Comp Meth in Appl Mech and Engng.,1980,23(1):67-83
[58]Li,W.,and Chen,C.J.On prediction of characteristics for vertical round buoyant jet in stably liner stratified environments[J].Hydr Res.1985,23(2):115-129
[59]王超,赵天台,严忠民.扩散器在宽浅江河中排放的流场与浓度场数值模拟[J].河海大学学报,1992,29(3),
[60]王超.同向多孔扩散器在宽浅江河中的诱导流场与浓度场分析[D].南京:河海大学,1990
[61]赵明登,郑邦民.横流中底部排污混合区的分析计算[J].武汉水利电力大学学报,1995,28(2):149-155
[62]杨志峰.潮汐流动中垂向排放近区数值模拟和优化差分方法研究[D].北京:清华大学,1989
[63]丁剡.完全深度平均紊流模型与非恒定天然河流中岸边排污的计算[D].北京:清华大学,1993
[64]杨志峰,周雪漪,许协庆.潮汐环境中垂向湍射流流场的数值模拟[J].水科学进展,1993,4(1)
[65]丁剡,周雪漪,李玉梁,余常昭.完全深度平均紊流模型及在潮流侧向排污计算中的应用[J].水利学报,1994(11):70-76
[66]周雪漪,阳坤,李玉梁,陈永灿.各向异性湍浮力模型在潮流底部排放计算中的应用[J].清华大学学报(自然科学版),1998,38(11):91-94
[67]李玉梁等.潮汐河流的水质模型及其在黄浦江中的应用[J].中国环境科学,1986,6(5)
[68]韩曾萃等.钱塘江河口非恒定污染带的数值模拟方法[J].河口与海岸工程,1987.6
[69]易家豪等.长江口外高桥城市污水排放数学模型研究[R].南京水利科学研究院河港所,1987.10
[70]李炜.环境水力学进展[M].武汉:武汉水利电力大学出版社,1999.6(第二版)
[71]金忠青.N-S方程的数值解和紊流模型[M].南京:河海大学出版社,1988
[72]Leschziner,M.A.,and Rodi,W.Calculation of annular and twin parallel jets using various discretization schemes and turbulence-model variation.Trans.of ASME[J].Fluids Engineering.1981.Vo1.103:352-360
[73]槐文信,李炜.环形和双孔射流吸附区的混合有限分析解[J].水动力学研究与进展A辑,1994,9(1):112-119
[74]槐文信,李炜.静止分层环境中圆形浮力射流全场特性的数值模拟[J].水动力学研究与进展,1993年增刊,1993.12
[75]槐文信,李炜,彭文启.横流中单圆孔紊动射流计算与特性分析[J].水利学报,1998(4)
[76]槐文信,李炜.双孔平面射流的数值模拟[J].水利学报,1994(11)
[77]张晓元,槐文信,李炜.多孔平面射流混合区流动的数值计算[J].应用基础与工程科学学报,1994,2(4):243-249
[78]金忠青.用标准k-ε模型求解二维紊动淹没射流[J].河海大学学报,1987,15(16)
[79]槐文信,杨晓亭.横流中多孔射流浓度场的特性[J].武汉水利电力大学学报,1997,30(5):16-20
[80]Yang,Z.F.,et al.Numerical modeling of the nearfield of side discharge into tidal flow in an open channel[M].In:J H W Lee,K Cheung,Environmental Hydraulics.Balkema Rotterdam Brookfield,1991.199-204
[81]Rodi,W.Turbulence model for environmental problems.In:Prediction Methods for Turbulent Flows[M].Hemisphere Publishing Cooperation,1980.260-349
[82]陈景仁.湍流模型及有限分析法[M].上海:上海交通大学出版社,1988
[83]李炜,槐文信.平面射流和浮力射流的数学模型及计算方法[J].水动力学研究与进展,1989,4(4):41-49
[84]江春波,许协庆.各向异性湍浮力流的三维有限元计算[J].水利学报,1991(7):8-18
[85]华祖林.三维代数应力通量模型及其在环境水力学中的应用.[D],南京:河海大学,1999.10
[86]Gatski,W,B.,and Speziale,C.G.On explicit algebraic stress models for complex turbulen flows[J].Fluid Mech.,1993,Vol.254:25-62
[87]阳坤.湍浮力模型及其在潮流底部排放计算中的应用[D].北京:清华大学,1997
[88]Larsen T,Petersen O,Chen H B.Numerical experiment on turbulent buoyant jets in flowing ambients.In:Proceedings of the 8th international conference on computational methods in water resources[C].Venice,Italy:1990.339-344
[89]Hwang R R,Chiang T P.Numerical simulation on turbulent buoyant jets in a cross-flow of stratified fluids[AI.In:Proceedings of the second international symposium on environmental hydraulics[C].Hong Kong,China:1999.109-115
[90]曾玉红,槐文信,流动环境中三维圆形垂直福利射流特性实验研究[J].实验流体力学,2005,9,19(3):39-46
[91]曾玉红,槐文信,圆形垂直浮力射流的稳定性与混合特性研究[J].应用数学和力学,2005,26(1):83-91
[92]曾玉红,槐文信,静止环境中垂直平面浮力射流稳定性和混合特性数值研究[J].水利学报,2004,9:56-62
[93]曾玉红,槐文信,静止环境中水平圆形浮力射流流动特性研究[J].华中科技大学学报(自然科学版),2005,33(11):90-92
[94]曾玉红,槐文信,横流中三维圆形垂直浮力射流特性数值分析[J].应用基础与工程科学学报,2005.13(2):120-124
[95]Lubbers C L,Brethouwer G,Boersma B J.Simulation of the mixing of a passive scalar in a round turbulent jet[J].Fluid Dynamic Research,2001,28(3):189-208
[96]Ferziger J H.Simulation and modeling in three-dimensional turbulent boundary layer:status and prospects[A].In:Processing of CFD Workshop[C].Tokyo:1994.22-33
[97]王福军.计算流体力学分-CFD软件原理与应用[M].北京:清华大学出版社,2004.9
[98]倪浩清,周力行,明渠温差异重流中湍浮力回流的数学模型[J].中国科学(A辑),1987(4):15-
[99]阳坤,洪益平,周雪漪,李玉梁.各向异性湍浮力模型的研究[J].应用数学和力学.2001(1):39-43
[100]Gatski T B,Speziale C G.On explicit algebraic stress models for complex turbulent flows[J].J Fluid Mech,1993,254(7):59-78.
[101]Pope S B.A more general effective-viscosity hypothesis[J].J Fluid Mech,1975,72(2):331-340
[102]Speziale C G.On nonlinear k-ι and k-ε models of turbulence[J].Fluid Mech,1987,178(5):450-475
[103]Rubinstein R,Baton J M.Nonlinear reynolds stress models and the renormalization group[J].Phys Fluids,1990,A2(8):1472-1476
[104]Shih T H,Liou W W,shabbir A,et al.A New k-ε eddy viscosity model for high Reynolds number turbulent flows[J].Computers Fluids,1995,24(3):227-238
[105]Fluent Inc.,FLUENT User's Guide[M].Fluent Inc.,2003
[106]徐国军.同流环境中热水紊动浮射流的研究[D].西安:西安理工大学,2007
[107]方神光.多矩形孔口紊动热水浮射流的研究[D].西安:西安理工大学,2002
