典型土木工程结构风荷载的数值模拟
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摘要
台风活动在我国十分频繁,随着现在全球气候变暖,气候变化越来越异常,台风的频率和强度都在增大。因此,对超高层的表面风压以及沿海一带的低矮房屋风荷载特性进行研究,对于减少我国沿海地区风灾损失以及国民经济的发展将具有十分重要意义。
本文首先基于CFX软件平台,按照实际尺寸建立了天津高银117的模型,采用RNG k ?ε湍流模型对平均基底荷载和表面风压进行了数值模拟研究。并且与风洞试验进行了对比,两种吻合较好。同时,通过数值模拟的方法方便地显示了流场的信息,对风压分布进行了机理分析。需要指出的是在断面棱角很明显并且靠近迎风面的地方,流体分离明显,局部风压很大,风压梯度变化剧烈,在进行围护结构设计的时候要采取必要的措施进行防范。
针对广东沿海一带一类比较典型的低矮建筑双坡房屋屋面平均风压进行了数值模拟,与风洞试验对比了对比,验证了数值模拟在低矮建筑中应用的正确性。研究了屋面上的屋脊和厝头等构筑件及其尺寸对屋面平均风压的影响,针对群体布局中最具典型代表性的两个双坡屋面并列布置之间的干扰效应进行了模拟计算和风洞实试验。结果显示:屋面边缘和屋脊地方负压较大,当加上由自重较大的混泥土制成的屋脊和厝头后,使得原来在这些地方分离的流体都转移到屋脊和厝头上,屋面负压的绝对值下降,是一种对屋面抗风有利的构建形式。屋脊的高度变化对整个屋面风压有一定的影响,不同风向角下影响情况是不同的。当风垂直于屋脊的时候影响作用最大,当风向与屋脊平行的时候,影响很小。两个低矮双坡房屋并列布置,存在明显干扰效应,各个部位的干扰效应不同,屋面最大负压干扰因子达到1.38,且干扰效应随着建筑间距的增大而减少,由数值模拟的风速场分析,可以发现并列布置干扰效应趋于消失的最大建筑间距。
Typhoons hit coastal areas of our country frequently. With global warming, climate changes more and more abnormally and typhoon frequency and intensity increase. Therefore, the research on high-rise surface wind pressure and wind load character of low houses in costal area is very significant to reduce damage caused by typhoons in costal areas in the country and maintain a good momentum of growthin the national economy.
Firstly,in this paper, the author uses CFX software platform to build the modal of Tianjin Gaoyin 117 according to its actual size and adopts RNG k ?εturbulence model to do numerical simulation for mean basal load and surface wind pressure. And compared with wind tunnel experiment,they agree well. At the same time, flow field information was displayed conveniently by numerical simulation, which does mechanism analysis to wind pressure distributions. It is needed to point out that there are obvious flow separation, big regional wind pressure and fierce wind pressure gradient change in edges are evident and near to the windward. Thus precautionary measures should be taken when palisade structure is designed.
Secondly, the author simulates the average wind pressure of roof numerically, which aims at typical low houses with double slopes in costal area of Guangdong province. Then the author compares its numerical simulation with wind tunnel experiment and verifies that it is right to use numerical simulation in research on low houses. The paper studies how ridge and fastigium and their sizes affect the average wind pressure of roof and the author simulates the disturbed effect between two parallel roofs with two slopes numerically and does wind tunnel experiment, which are the most typical in group low buildings. The results show that the edge and ridge has great negative pressure and building ridge and fastigium made of concrete on the roof is a effective way for wind resistance of roof because the concrete has greater dead weight which results in the fluid gathering into the ridge and fastigium where the fluid separates and the absolute value of the negative pressure of the roof going down. The changing of the height of ridge effects wind pressure of the whole roof to some degree but depends on wind directions. Wind pressure of the whole roof is affected most when wind is perpendicular to ridge and it is affected least when wind is parallel to ridge. When two low houses with double slopes are built in parallel there has obvious disturbed effect and different parts have different disturbed effects. The biggest roofing negative pressure disturbance reaches 1.38 and the disturbed effect goes down with the distance broadening between the two parallel houses. Analyzing wind vector by numerical simulation, it can be found that the disturbance effect has a tendency to disappear when the two low houses are built in the biggest parallel distance.
本文首先基于CFX软件平台,按照实际尺寸建立了天津高银117的模型,采用RNG k ?ε湍流模型对平均基底荷载和表面风压进行了数值模拟研究。并且与风洞试验进行了对比,两种吻合较好。同时,通过数值模拟的方法方便地显示了流场的信息,对风压分布进行了机理分析。需要指出的是在断面棱角很明显并且靠近迎风面的地方,流体分离明显,局部风压很大,风压梯度变化剧烈,在进行围护结构设计的时候要采取必要的措施进行防范。
针对广东沿海一带一类比较典型的低矮建筑双坡房屋屋面平均风压进行了数值模拟,与风洞试验对比了对比,验证了数值模拟在低矮建筑中应用的正确性。研究了屋面上的屋脊和厝头等构筑件及其尺寸对屋面平均风压的影响,针对群体布局中最具典型代表性的两个双坡屋面并列布置之间的干扰效应进行了模拟计算和风洞实试验。结果显示:屋面边缘和屋脊地方负压较大,当加上由自重较大的混泥土制成的屋脊和厝头后,使得原来在这些地方分离的流体都转移到屋脊和厝头上,屋面负压的绝对值下降,是一种对屋面抗风有利的构建形式。屋脊的高度变化对整个屋面风压有一定的影响,不同风向角下影响情况是不同的。当风垂直于屋脊的时候影响作用最大,当风向与屋脊平行的时候,影响很小。两个低矮双坡房屋并列布置,存在明显干扰效应,各个部位的干扰效应不同,屋面最大负压干扰因子达到1.38,且干扰效应随着建筑间距的增大而减少,由数值模拟的风速场分析,可以发现并列布置干扰效应趋于消失的最大建筑间距。
Typhoons hit coastal areas of our country frequently. With global warming, climate changes more and more abnormally and typhoon frequency and intensity increase. Therefore, the research on high-rise surface wind pressure and wind load character of low houses in costal area is very significant to reduce damage caused by typhoons in costal areas in the country and maintain a good momentum of growthin the national economy.
Firstly,in this paper, the author uses CFX software platform to build the modal of Tianjin Gaoyin 117 according to its actual size and adopts RNG k ?εturbulence model to do numerical simulation for mean basal load and surface wind pressure. And compared with wind tunnel experiment,they agree well. At the same time, flow field information was displayed conveniently by numerical simulation, which does mechanism analysis to wind pressure distributions. It is needed to point out that there are obvious flow separation, big regional wind pressure and fierce wind pressure gradient change in edges are evident and near to the windward. Thus precautionary measures should be taken when palisade structure is designed.
Secondly, the author simulates the average wind pressure of roof numerically, which aims at typical low houses with double slopes in costal area of Guangdong province. Then the author compares its numerical simulation with wind tunnel experiment and verifies that it is right to use numerical simulation in research on low houses. The paper studies how ridge and fastigium and their sizes affect the average wind pressure of roof and the author simulates the disturbed effect between two parallel roofs with two slopes numerically and does wind tunnel experiment, which are the most typical in group low buildings. The results show that the edge and ridge has great negative pressure and building ridge and fastigium made of concrete on the roof is a effective way for wind resistance of roof because the concrete has greater dead weight which results in the fluid gathering into the ridge and fastigium where the fluid separates and the absolute value of the negative pressure of the roof going down. The changing of the height of ridge effects wind pressure of the whole roof to some degree but depends on wind directions. Wind pressure of the whole roof is affected most when wind is perpendicular to ridge and it is affected least when wind is parallel to ridge. When two low houses with double slopes are built in parallel there has obvious disturbed effect and different parts have different disturbed effects. The biggest roofing negative pressure disturbance reaches 1.38 and the disturbed effect goes down with the distance broadening between the two parallel houses. Analyzing wind vector by numerical simulation, it can be found that the disturbance effect has a tendency to disappear when the two low houses are built in the biggest parallel distance.
引文
[1]台风与台风灾害.中国防汛抗洪.2010.5
[2] S.Murakami,A.Mochida.Three Dimensional Numerical Simulation of Air flow Around a Cubic Model By Means of Large Eddy Simulation..Journal of Wind Engineering and Industrial Aerodynamics. 1987,25:291-305
[3] S.Murakami,A.Mochida.Three Dimensional Numerical Simulation of Turbulent Flow Around Building Using theκ-εTurbulent Model.Building and Environment,1989,24:51-64
[4] S.Murakami. Comparision of Various Turbulence Models Applied To Abluff Body. Journal of Wind Engineering and Industrial Aerodynamics,1993,46&47:21-36.
[5] D.A.Parerson,C.J. Apelt. Simulation of Flow Past A Cube In A Turbulent Boundary Layer. Journal of Wind Engineering and Industrial Aerodynamics,1990,35:149-176.
[6] D.Delaunay,D.Lakehal,D.pierrat. Numerical approach for wind loads prediction on buildings and structures. Journal of Wind Engineering and Industrial Aerodynamics 57(1995)307-321.
[7] Y.Li,T.Stathopulos. Numerical Evaluation of Wind-Induced Dispersion of Pollutants Around A Building. Journal of Wind Engineering and Industrial Aerodynamics,1997,67:757-766.
[8] M.Tutar G.Oguz. Large Eddy Simulation of Wind Flow Around Parallel Buildings With Varying Configuration. Fluid Dynamics Research,2002,9:289-315.
[9] D.M.Hargreaves,N.G.Wright. On The Use of The k?εModel In Commercial CFD Software To Model The Neutral Atmospheric Boundary Layer. Journal of Wind Engineering and Industrial Aerodynamics,2007,95:355-369
[10]殷惠君,张其林,周志勇.标准低矮建筑TTU三维定常风场数值模拟研究[J].工程力学,2007,24(2):139-145.
[11]顾明,杨伟,黄鹏,罗攀. TTU标模风压数值模拟及试验对比[J],同济大学学报(自然科学版), 2006,34(12):1563-1567
[12] Aishe Zhang,Guilan Gao,Ling Zhang. Numerical Simulation of The Wind Field Around Different Building Arrangemengs. Journal of Wind Engineering and Industrial Aerodynamics,2005,93:891-904.
[13] Aishe Zhang,Ming Gu. Wind Tunnel Tests And Numerical Simulations of Wind Pressures On Buildings In Staggered Arrangement.Journal of Wind Engineering and Industrial Aerodynamics,2005,93:891-904.
[14] Y.Gao,W.K.Chow. Numerical Studies On Air Flow Around A Cube. Journal of Wind Engineering and Industrial Aerodynamics,2005,93:115-135.
[15]杨伟,金新阳,顾明,陈素琴.风工程数值模拟中平衡大气边界层的研究与应用[J].土木工程学报,2007,40(2):1-5.
[16]焦燏烽,赵果,陈水福.低层四坡屋面建筑群风环境特性的数值模拟[J.力学与实践,2008,30(5):86-89.
[17] Wei Yang,Yong Quan,Xinyang Jin,Yukio Tamura Ming Gu. Influences of Equilibrium Atmosphere Boundary Layer And Turblence Parameter On Wind Loads of Low-rise Buildings. Journal of Wind Engineering and Industrial Aerodynamics,2008,96:2080-2092.
[18]顾磊,齐宏拓,刘红军,傅学怡.奥运网球中心赛场风荷载和风环境数值模拟分析[J].建筑结构学报,2009,30(3):134-143.
[19]顾明,黄强,黄鹏,全涌,谢壮宁,带挑檐低层房屋屋面平均风压的数值模拟研究,建筑结构学报,2009,30(5): 205-211.
[20] John D.Anderson.计算流体力学基础及其应用.吴颂平,刘赵淼译.北京:机械工业出版社,2008
[21]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
[22]龙天渝,苏亚欣,向文英,何川.计算流体力学.重庆:重庆大学出版社,2007
[23]杨伟.基于RANS的结构风荷载和响应的数值模拟研究.同济大学,2004.
[24] W.Jester,Y.Kallinderis. Numerical Study of Incompressible Flow About Fixed Cylinder Pairs.Journal of Fluids And Structures,2003,17:561-577.
[25] I.Robertson,L.Li,S.J.Sherwim,P.W.Bearman.A Numerical Study of Rorational And Transverse Galloping Rectangular Bodys.Journal of Fluid And Structures,2003,17:681-699.
[26] D.J.J.Lechlercq,C.J.Doolan. The Interaction of A Bluff Body With A Vortex Wake. Journal of Fluids And Structures,2009,25:867-888.
[27] G.V.Iungo,G.Buresti.Experimental Investigation On The Aerodynamic Loads And Wake Flow Features of Low Aspect-ratio Triangular Prism At Different Wind Directions. Journal of Fluid And Structures,2009,25:1119-1135.
[28] M.Cheng,D.S.Whyte,J.Lou. Numerical Simulation of Flow Around A Square Cylinder In Uniform-shear Flow. Journal of Fluid And Structures,2007,23:207-226.
[29] E.Konstantinidis,S.Balabani. Symmetric Vortex Shedding In The Near Wake of A Circular Cylinder Due to Streamwise Perturbations. Journal of Fluid And Structures,2007,23:1047-1063.
[30] G.R.S.Assi,P.W.Bearman,N.Kitney.Low Drag Solutions For Suppressing Vortex-induced Vibration of Circular Cylinders. Journal of Fluid And Structures,2009,25:666-675.
[31] C.H.Kuo,C.C.Chen. Passive Control of Wake Flow By Two Small Control Cylinders At Reynolds Number 80. Journal of Fluid And Structures,2009,27:1021-1028.
[32]方平治,顾明.高雷诺数条件下二维方柱涡激振动的数值模拟[J].同济大学学报(自然科学版),2008,36(2):162-165.
[33]方平治,杜明侠,顾明.两自由度椭圆柱体涡激振动的数值模拟[J].振动与冲击,2009,28(1):52-55.
[34]方平治,顾明,谈建国.典型2维柱体涡激振动的数值模拟研究[J].同济大学学报(自然科学版),2009,37(3):863-866.
[35]徐枫,欧进萍.方柱非定常绕流与涡激振动的数值模拟[J].东南大学学报(自然科学版),2005,35(7):36-39.
[36]徐枫,欧进萍,肖仪清.方柱流致横向振动的CFD数值模拟[J].哈尔滨工业大学学报,2008,40(12):1850-1854.
[37]徐枫,欧进萍,肖仪清.不同截面形状柱体流致振动的CFD数值模拟研究[J].工程力学,2009,26(4):7-15.
[38]李寿英,顾明.斜、直圆柱绕流的CFD模拟[J].空气动力学学报,2005,23(2):222-227.
[39]谢壮宁,石碧青,倪振华.天津高银117工程抗风研究:风洞试验和响应计算[R].汕头:汕头大学风洞试实验室.
[40] V.Yakhot,S.A.Orazg.Renormalization Group Analysis of Turbulence:Basic Theory.J.Scient Comput.1:3-11,1986
[41]王绍文.广东沿海典型低矮建筑调研与风荷载特性的实验研究,汕头大学硕士学位论文.2009.
[42]刘帅. TTU标模及平顶罩棚类低矮建筑的风洞试验研究,汕头大学硕士学位论文.2009.
[43]周绪红,聂少锋,周天华,龚焮.低层双坡屋面建筑三维定常风场的数值模拟[J].工程力学,2010,27(3):19-29.
[44]鄂玉良.典型群体低矮建筑的风压分布特征,第十四届全国结构风工程学术会议,2009.8
[2] S.Murakami,A.Mochida.Three Dimensional Numerical Simulation of Air flow Around a Cubic Model By Means of Large Eddy Simulation..Journal of Wind Engineering and Industrial Aerodynamics. 1987,25:291-305
[3] S.Murakami,A.Mochida.Three Dimensional Numerical Simulation of Turbulent Flow Around Building Using theκ-εTurbulent Model.Building and Environment,1989,24:51-64
[4] S.Murakami. Comparision of Various Turbulence Models Applied To Abluff Body. Journal of Wind Engineering and Industrial Aerodynamics,1993,46&47:21-36.
[5] D.A.Parerson,C.J. Apelt. Simulation of Flow Past A Cube In A Turbulent Boundary Layer. Journal of Wind Engineering and Industrial Aerodynamics,1990,35:149-176.
[6] D.Delaunay,D.Lakehal,D.pierrat. Numerical approach for wind loads prediction on buildings and structures. Journal of Wind Engineering and Industrial Aerodynamics 57(1995)307-321.
[7] Y.Li,T.Stathopulos. Numerical Evaluation of Wind-Induced Dispersion of Pollutants Around A Building. Journal of Wind Engineering and Industrial Aerodynamics,1997,67:757-766.
[8] M.Tutar G.Oguz. Large Eddy Simulation of Wind Flow Around Parallel Buildings With Varying Configuration. Fluid Dynamics Research,2002,9:289-315.
[9] D.M.Hargreaves,N.G.Wright. On The Use of The k?εModel In Commercial CFD Software To Model The Neutral Atmospheric Boundary Layer. Journal of Wind Engineering and Industrial Aerodynamics,2007,95:355-369
[10]殷惠君,张其林,周志勇.标准低矮建筑TTU三维定常风场数值模拟研究[J].工程力学,2007,24(2):139-145.
[11]顾明,杨伟,黄鹏,罗攀. TTU标模风压数值模拟及试验对比[J],同济大学学报(自然科学版), 2006,34(12):1563-1567
[12] Aishe Zhang,Guilan Gao,Ling Zhang. Numerical Simulation of The Wind Field Around Different Building Arrangemengs. Journal of Wind Engineering and Industrial Aerodynamics,2005,93:891-904.
[13] Aishe Zhang,Ming Gu. Wind Tunnel Tests And Numerical Simulations of Wind Pressures On Buildings In Staggered Arrangement.Journal of Wind Engineering and Industrial Aerodynamics,2005,93:891-904.
[14] Y.Gao,W.K.Chow. Numerical Studies On Air Flow Around A Cube. Journal of Wind Engineering and Industrial Aerodynamics,2005,93:115-135.
[15]杨伟,金新阳,顾明,陈素琴.风工程数值模拟中平衡大气边界层的研究与应用[J].土木工程学报,2007,40(2):1-5.
[16]焦燏烽,赵果,陈水福.低层四坡屋面建筑群风环境特性的数值模拟[J.力学与实践,2008,30(5):86-89.
[17] Wei Yang,Yong Quan,Xinyang Jin,Yukio Tamura Ming Gu. Influences of Equilibrium Atmosphere Boundary Layer And Turblence Parameter On Wind Loads of Low-rise Buildings. Journal of Wind Engineering and Industrial Aerodynamics,2008,96:2080-2092.
[18]顾磊,齐宏拓,刘红军,傅学怡.奥运网球中心赛场风荷载和风环境数值模拟分析[J].建筑结构学报,2009,30(3):134-143.
[19]顾明,黄强,黄鹏,全涌,谢壮宁,带挑檐低层房屋屋面平均风压的数值模拟研究,建筑结构学报,2009,30(5): 205-211.
[20] John D.Anderson.计算流体力学基础及其应用.吴颂平,刘赵淼译.北京:机械工业出版社,2008
[21]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
[22]龙天渝,苏亚欣,向文英,何川.计算流体力学.重庆:重庆大学出版社,2007
[23]杨伟.基于RANS的结构风荷载和响应的数值模拟研究.同济大学,2004.
[24] W.Jester,Y.Kallinderis. Numerical Study of Incompressible Flow About Fixed Cylinder Pairs.Journal of Fluids And Structures,2003,17:561-577.
[25] I.Robertson,L.Li,S.J.Sherwim,P.W.Bearman.A Numerical Study of Rorational And Transverse Galloping Rectangular Bodys.Journal of Fluid And Structures,2003,17:681-699.
[26] D.J.J.Lechlercq,C.J.Doolan. The Interaction of A Bluff Body With A Vortex Wake. Journal of Fluids And Structures,2009,25:867-888.
[27] G.V.Iungo,G.Buresti.Experimental Investigation On The Aerodynamic Loads And Wake Flow Features of Low Aspect-ratio Triangular Prism At Different Wind Directions. Journal of Fluid And Structures,2009,25:1119-1135.
[28] M.Cheng,D.S.Whyte,J.Lou. Numerical Simulation of Flow Around A Square Cylinder In Uniform-shear Flow. Journal of Fluid And Structures,2007,23:207-226.
[29] E.Konstantinidis,S.Balabani. Symmetric Vortex Shedding In The Near Wake of A Circular Cylinder Due to Streamwise Perturbations. Journal of Fluid And Structures,2007,23:1047-1063.
[30] G.R.S.Assi,P.W.Bearman,N.Kitney.Low Drag Solutions For Suppressing Vortex-induced Vibration of Circular Cylinders. Journal of Fluid And Structures,2009,25:666-675.
[31] C.H.Kuo,C.C.Chen. Passive Control of Wake Flow By Two Small Control Cylinders At Reynolds Number 80. Journal of Fluid And Structures,2009,27:1021-1028.
[32]方平治,顾明.高雷诺数条件下二维方柱涡激振动的数值模拟[J].同济大学学报(自然科学版),2008,36(2):162-165.
[33]方平治,杜明侠,顾明.两自由度椭圆柱体涡激振动的数值模拟[J].振动与冲击,2009,28(1):52-55.
[34]方平治,顾明,谈建国.典型2维柱体涡激振动的数值模拟研究[J].同济大学学报(自然科学版),2009,37(3):863-866.
[35]徐枫,欧进萍.方柱非定常绕流与涡激振动的数值模拟[J].东南大学学报(自然科学版),2005,35(7):36-39.
[36]徐枫,欧进萍,肖仪清.方柱流致横向振动的CFD数值模拟[J].哈尔滨工业大学学报,2008,40(12):1850-1854.
[37]徐枫,欧进萍,肖仪清.不同截面形状柱体流致振动的CFD数值模拟研究[J].工程力学,2009,26(4):7-15.
[38]李寿英,顾明.斜、直圆柱绕流的CFD模拟[J].空气动力学学报,2005,23(2):222-227.
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