植物“柔性坝”过流水动力学特性及其固沙机理研究
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摘要
为了解决我国的河流泥沙灾害,尤其是新疆的防沙、治沙和水土流失问题,本文较系统地总结了有植被水流问题的研究现状。根据试验资料详细分析了有无植物坝时的二维流场变化情况,提出按种树后水流流速的变化将植物“柔性坝”前后的水流沿纵向进行分区,以便直观地了解植物“柔性坝”对水流的作用及其拦沙、减蚀的主要原因；分析了水流边界条件如底坡、糙率等对植物“柔性坝”拦沙效果的影响；对不同布置形式和排列方式的植物“柔性坝”进行了多组次对比,分析了坝长及种植密度对其拦沙效果的影响,并在此基础上进行了单坝的坝型优选。
根据清水试验资料,进行了植物“柔性坝”水流特性的研究。植物坝的存在干扰了原有的水流流态,使坝上游水深增加,水流流速减小,同时还增大河床糙率,削减了床面剪应力。说明植物坝可以减小泥沙的起动拖曳力,降低上游泥沙的起动频率,并能使运动的泥沙在坝上游沉积下来。而后根据含沙水流的试验资料,通过对植树前后单颗粒泥沙的运动变化、坝前泥沙的淤积形态以及截沙率的分析,证明了植物坝具有拦截泥沙的作用,而且沟道底坡越小拦沙效果越好。之后对植物坝前上游段推移质泥沙的输移特性进行了研究,初步探明了植物“柔性坝”的固沙机理。
通过室内物理模型试验的初期成果,对植物“柔性坝”过流时的水动力学特性进行了数值研究,建立了植物水流动力学方程,并利用F1uent软件进行了数值计算。文中分析计算结果并与模型试验结果进行了比较,验证了所选的数学模型和数值计算方法的可靠性。这对植物“柔性坝”应用于实际工程具有十分重要的意义。最后运用一维水沙数学模型,进行了植物坝前壅水区内河床冲淤计算的数值模拟。结果表明,计算值与实测值吻合较好,具有一定的实用价值。
In order to solve river sediment disaster in our country, particularly resolve sand prevention, training for sediment and soil erosion problems in Xinjiang, this paper systematically concludes study the present condition of flow with plant. According to variations of two-dimensional flow after planted flexible dam, four districts along longitude are divided:inlet district, backwater district, plant dam district and recovery district, so as to more directly understand main reason of sediment retention of plant flexible dam. Flow boundary factors such as bottom slope, roughness and plant factors such as length and density of dam are analyzed to find how these factors effluence on the effect of sediment retention of plant dam. Then better type of plant dam is selected based on comparison of different type of dam.
According to the clear water experiment data, studies flow characteristics of vegetation "flexible dam". Vegetation dam will interfere original flow pattern and make water depth of dam's upper reaches rise, flow velocity let down, bed roughness rise and bed shear stress let down. These show that vegetation dam can reduce starting drag force and starting frequency of sediment in upper reaches. And can make athletic sediment deposit. Then according to the suspension current experiment data, by analyzing motion change of single particle before and after planting, sediment's feature in the front of dam and trapping efficiency, proves that vegetation dam can intercept sediment, especially gentle slopes are better. Lastly, studies transportation characteristic of bed load sediment of upstream end before vegetation dam. Preliminarily clear sand-binding mechanism of vegetation "flexible dam".
And by the indoor physical model experiment's early result, proceeded number research to overflowing hydrodynamic characteristics of vegetation "flexible dam", established plant hydrodynamics equation, and proceeded the number calculation by fluent. It analyze the calculation result and proceeded the comparison to the experiment with model in the text, verified the dependable of the mathematics model and number calculation method for choosing. It's very important meaning to apply vegetation "flexible dam" in the actual engineering. Lastly, studies transportation characteristic of bed load sediment of upstream end before vegetation dam, and base on the experiment, utilizing one-dimensional flow sediment mathematical model, and simulates bed silt calculating before vegetation dam. It shows that calculating result is similar to observation result, and has the certainly practical value.
根据清水试验资料,进行了植物“柔性坝”水流特性的研究。植物坝的存在干扰了原有的水流流态,使坝上游水深增加,水流流速减小,同时还增大河床糙率,削减了床面剪应力。说明植物坝可以减小泥沙的起动拖曳力,降低上游泥沙的起动频率,并能使运动的泥沙在坝上游沉积下来。而后根据含沙水流的试验资料,通过对植树前后单颗粒泥沙的运动变化、坝前泥沙的淤积形态以及截沙率的分析,证明了植物坝具有拦截泥沙的作用,而且沟道底坡越小拦沙效果越好。之后对植物坝前上游段推移质泥沙的输移特性进行了研究,初步探明了植物“柔性坝”的固沙机理。
通过室内物理模型试验的初期成果,对植物“柔性坝”过流时的水动力学特性进行了数值研究,建立了植物水流动力学方程,并利用F1uent软件进行了数值计算。文中分析计算结果并与模型试验结果进行了比较,验证了所选的数学模型和数值计算方法的可靠性。这对植物“柔性坝”应用于实际工程具有十分重要的意义。最后运用一维水沙数学模型,进行了植物坝前壅水区内河床冲淤计算的数值模拟。结果表明,计算值与实测值吻合较好,具有一定的实用价值。
In order to solve river sediment disaster in our country, particularly resolve sand prevention, training for sediment and soil erosion problems in Xinjiang, this paper systematically concludes study the present condition of flow with plant. According to variations of two-dimensional flow after planted flexible dam, four districts along longitude are divided:inlet district, backwater district, plant dam district and recovery district, so as to more directly understand main reason of sediment retention of plant flexible dam. Flow boundary factors such as bottom slope, roughness and plant factors such as length and density of dam are analyzed to find how these factors effluence on the effect of sediment retention of plant dam. Then better type of plant dam is selected based on comparison of different type of dam.
According to the clear water experiment data, studies flow characteristics of vegetation "flexible dam". Vegetation dam will interfere original flow pattern and make water depth of dam's upper reaches rise, flow velocity let down, bed roughness rise and bed shear stress let down. These show that vegetation dam can reduce starting drag force and starting frequency of sediment in upper reaches. And can make athletic sediment deposit. Then according to the suspension current experiment data, by analyzing motion change of single particle before and after planting, sediment's feature in the front of dam and trapping efficiency, proves that vegetation dam can intercept sediment, especially gentle slopes are better. Lastly, studies transportation characteristic of bed load sediment of upstream end before vegetation dam. Preliminarily clear sand-binding mechanism of vegetation "flexible dam".
And by the indoor physical model experiment's early result, proceeded number research to overflowing hydrodynamic characteristics of vegetation "flexible dam", established plant hydrodynamics equation, and proceeded the number calculation by fluent. It analyze the calculation result and proceeded the comparison to the experiment with model in the text, verified the dependable of the mathematics model and number calculation method for choosing. It's very important meaning to apply vegetation "flexible dam" in the actual engineering. Lastly, studies transportation characteristic of bed load sediment of upstream end before vegetation dam, and base on the experiment, utilizing one-dimensional flow sediment mathematical model, and simulates bed silt calculating before vegetation dam. It shows that calculating result is similar to observation result, and has the certainly practical value.
引文
[1]毕慈芬.黄土高原基岩产沙区治理对策探讨[J].泥沙研究,2001,(4)：1-5.
[2]发展沟道人工湿地改善基岩产沙区生态[J].中国水土保持,2001,(5)：6-7.
[3]毕慈芬,于倬德,李桂芬.治理砒砂岩地区水土流失的新设想[C].第二届海峡两岸水利科技交流研讨会论文集,台北,1996.
[4]黑龙江省防护林研究所等.中国沙棘[M].银川：宁夏人民出版社,2001,04.
[5]Vassitios A.Tsihrtintzis, Edgear E.Madiedo. Hydraulic Resistance Determination in Marsh Wetlands[J]. Water Resources Management,2000(14):285-309.
[6]钮茂生.为国分忧,为民造福,大力发展沙棘事业[J].中国水土保持,1991,(3).
[7]毕慈芬.黄土高原基岩产沙区治理对策探讨[J].泥沙研究,2001,(4)：1-5.
[8]Li Zhuo. The Effects of Forest in Controlling Gully Erosion[J]. Erosion. Debris. Flows and Environment in Mountain Regions IAHS Published, No.290,1991.
[9]Kouwen N, Li R M,Simons D B. Flow resistance in vegetated waterways [J]. Trans ASCE,1981,24(3):684～698.
[10]Hsieh T. Resistance of Cylinder Piers in Open-channel Flow[J]. J. Hydraul. Div., Am. Soc. Civ. Eng.,1964,90(HY1):161-173.
[11]Ruh-Ming Li and H. W. Shen. Effect of Tall Vegetations on Flow and Sediment [J]. Journal of Hydraulics Division,1973,99 (5):793-814.
[12]Dunn C, Lopez F, Garcia M. Mean Flow and Turbulence in a Laboratory Channel with Simulated Vegetation[R]. Civil Engineering Studies Hydra Engineering Series No.51, Dept. of Civil Engrg., Univ. of Llino is at Urbana-Champaign,1996.
[13]Pasch E, Rouve G. Overbank Flow with Vegetatively Roughened Flood Plains [J]. J. Hydr. Engrg., ASCE,1985,119(9):1262-1278.
[14]Stephen E. Darby effect if riparian Vegetation on Flow Resistance and Flood Potential [J]. J. Hydr. Engrg., ASCE,1999,125(5):443-454.
[15]Ree W.O., Palmer V. J. Flow of Water in Channels Protected by Vegetative Lining[C]. U. S. Dept of Agriculture Soil Conservation Service. Tech. Bull. Washington. D. C,1949, 967.
[16]Kouwen N., Li R. M., Simons. D. B. Flow Resistance in Vegetated Waterways[J]. Trans. ASCE,1981,24(3):684-698.
[17]Fei-yong Chen. Turbulent Shear Flow in Shallow Open Channel with Training Structures[D].东京技术学院博士论文,日本东京,1996.
[18]Kouwen N., Li R. M., Simons. D. B. Flow Resistance in Vegetated Waterways[J]. Trans. ASCE,1981,24(3):684-698.
[19]Kouwen N. Modern Approach to Design of Grassed Channels [J]. J. Irrig. Drain Eng.,1992, 118(5):713-743.
[20]时钟.海岸盐沼植物单向恒定水流流速剖面[J].泥沙研究,1997,(3)
[21]时钟.海岸盐沼冠层水流平均流速分布的试验研究[J].海洋工程,2001,(3)
[22]蔡金德、黄本胜.河滩种树对河道行洪的影响,四川省工程水力学及泥沙问题学术讨论会论文,丰都.1994.3.
[23]黄本胜.漫滩水流问题及其研究进展.94全国水动力研讨会文集,海洋出版社,1994
[24]Huang Bensheng, Lin Shuzhong, Lai Guanwen and Qiujing,. Hydraulics of Compound Channel with Vegetated Floodplains[J]. Journal of Hydrodynamics Se. B,2002,115(1).
[25]石月珍.河滩种树的复式断面河道水流特性研究[D].[硕士学位论文].新疆乌鲁木齐：新疆农业大学,2002.
[26]石月珍,黄本胜.有植被的河渠水流问题的研究现状进展[C].中国水力2002年会议论文集.西安理工大学中国水利学会水力学专业委员会,2002年4月.
[27]王忖.有植被的河道水流试验研究[D].[硕士学位论文].江苏南京：河海大学,2003.
[28]毕慈芬,李桂芬,于倬德,等.砒砂岩地区植物“柔性坝”试验研究阶段总报[R].水利部黄委会上中游管理局,1999.
[29]拾兵,曹叔尤.植物治沙动力学[M].青岛：青岛海洋大学出版社,2000,11.
[30]拾兵.植物治沙力学机理及河宽动力调整研究[D].[博士学位论文].四川成都：四川大学,1998.
[31]M Fathi-Maghadam and N Kouwen. Nonrigid Nonsubmerged Vegetative Roughness on Floodplains. J. Hydr. Engrg., ASCE,1997,123(1):51-57.
[32]邱秀云,阿不都外力,程艳,等.植物“柔性坝”对水流影响的试验研究[J].水利水电技术,2003,34(9)：62-65.
[33]程艳.植物“柔性坝”水流特性的试验研究[D].[硕士学位论文].新疆乌鲁木齐：新疆农业大学,2004.
[34]阎洁,周著,邱秀云,等.植物“柔性坝”阻水试验及固沙机理分析[J].新疆农业大学学报,2004,27(3)：40-45.
[35]Naot D, Nezu I, Nakagawa H. Hydrodynamic Behavior of Partly Vegetated Open Channels [J]. J. Hydr. Engrg., ASCE,1996,122(11):625-663.
[36]Dan N, Iehisa Nezu I, Hiroji Nakagawa H. Unstable Pattern in Partly Vegetated Open Channels[J]. J. Hydr. Engrg., ASCE,1996,122(11):671-673.
[37]Fei-yong Chen. Turbulent Shear Flow in Shallow Open Channel with Training Structures [D].东京技术学院博士论文,日本东京,1996.
[38]Nadaoka K, Yagi H. Shallow-water Turbulence Modeling and Horizontal Large-eddy Computation of river flow[J]. J Hydraul Eng,1988,124(5).
[39]宿晓辉,张建新,李志伟,等.带有植物的河道水流浅水紊流运动大涡模拟[J].大连理工大学学报.2003,(2)：223-230.
[40]程莉.植物护岸条件下河道水流的数值模拟[D].[硕士学位论文].江苏南京：河海大学,2002.
[41]张二骏.流体数值模拟[J].河海大学科技情报,1990,11
[42]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,1989.
[43]谭维炎.计算浅水动力学—有限体积法的运用[M].北京：清华大学出版社,1998.
[44]M.G.Khublaryan,A.P Frolov,V N.Zyryanov. Modeling water flow in the presence of higher vegetation. Water Resources,2004,31 (6):617-622.
[45]章本照.流体力学中的有限元方法[M].北京：机械工业出版社,1986.
[46]苏铭德等.计算流体力学基础[M].北京：清华大学出版社,1989.
[47]马法三.计算流体力学—有限元法[M].南京：河海大学出版社,1989.
[48]W. H. Graf. Hydraulics of Sediment Transport [M]. MCGraw-Hill Book Company, New York,1973.
[49]H. A. Einstein. The Bed-load function for Sediment Transportation in Open Channel Flows [J]. U. S. Dept. Agriculture, Soil Conservation Ser. Thch Bull.1950, (76).
[50]王文江.植物柔性坝在集水区治理上之应用[M].美国：美国MUL TECH工程咨询公司,2003.
[2]发展沟道人工湿地改善基岩产沙区生态[J].中国水土保持,2001,(5)：6-7.
[3]毕慈芬,于倬德,李桂芬.治理砒砂岩地区水土流失的新设想[C].第二届海峡两岸水利科技交流研讨会论文集,台北,1996.
[4]黑龙江省防护林研究所等.中国沙棘[M].银川：宁夏人民出版社,2001,04.
[5]Vassitios A.Tsihrtintzis, Edgear E.Madiedo. Hydraulic Resistance Determination in Marsh Wetlands[J]. Water Resources Management,2000(14):285-309.
[6]钮茂生.为国分忧,为民造福,大力发展沙棘事业[J].中国水土保持,1991,(3).
[7]毕慈芬.黄土高原基岩产沙区治理对策探讨[J].泥沙研究,2001,(4)：1-5.
[8]Li Zhuo. The Effects of Forest in Controlling Gully Erosion[J]. Erosion. Debris. Flows and Environment in Mountain Regions IAHS Published, No.290,1991.
[9]Kouwen N, Li R M,Simons D B. Flow resistance in vegetated waterways [J]. Trans ASCE,1981,24(3):684～698.
[10]Hsieh T. Resistance of Cylinder Piers in Open-channel Flow[J]. J. Hydraul. Div., Am. Soc. Civ. Eng.,1964,90(HY1):161-173.
[11]Ruh-Ming Li and H. W. Shen. Effect of Tall Vegetations on Flow and Sediment [J]. Journal of Hydraulics Division,1973,99 (5):793-814.
[12]Dunn C, Lopez F, Garcia M. Mean Flow and Turbulence in a Laboratory Channel with Simulated Vegetation[R]. Civil Engineering Studies Hydra Engineering Series No.51, Dept. of Civil Engrg., Univ. of Llino is at Urbana-Champaign,1996.
[13]Pasch E, Rouve G. Overbank Flow with Vegetatively Roughened Flood Plains [J]. J. Hydr. Engrg., ASCE,1985,119(9):1262-1278.
[14]Stephen E. Darby effect if riparian Vegetation on Flow Resistance and Flood Potential [J]. J. Hydr. Engrg., ASCE,1999,125(5):443-454.
[15]Ree W.O., Palmer V. J. Flow of Water in Channels Protected by Vegetative Lining[C]. U. S. Dept of Agriculture Soil Conservation Service. Tech. Bull. Washington. D. C,1949, 967.
[16]Kouwen N., Li R. M., Simons. D. B. Flow Resistance in Vegetated Waterways[J]. Trans. ASCE,1981,24(3):684-698.
[17]Fei-yong Chen. Turbulent Shear Flow in Shallow Open Channel with Training Structures[D].东京技术学院博士论文,日本东京,1996.
[18]Kouwen N., Li R. M., Simons. D. B. Flow Resistance in Vegetated Waterways[J]. Trans. ASCE,1981,24(3):684-698.
[19]Kouwen N. Modern Approach to Design of Grassed Channels [J]. J. Irrig. Drain Eng.,1992, 118(5):713-743.
[20]时钟.海岸盐沼植物单向恒定水流流速剖面[J].泥沙研究,1997,(3)
[21]时钟.海岸盐沼冠层水流平均流速分布的试验研究[J].海洋工程,2001,(3)
[22]蔡金德、黄本胜.河滩种树对河道行洪的影响,四川省工程水力学及泥沙问题学术讨论会论文,丰都.1994.3.
[23]黄本胜.漫滩水流问题及其研究进展.94全国水动力研讨会文集,海洋出版社,1994
[24]Huang Bensheng, Lin Shuzhong, Lai Guanwen and Qiujing,. Hydraulics of Compound Channel with Vegetated Floodplains[J]. Journal of Hydrodynamics Se. B,2002,115(1).
[25]石月珍.河滩种树的复式断面河道水流特性研究[D].[硕士学位论文].新疆乌鲁木齐：新疆农业大学,2002.
[26]石月珍,黄本胜.有植被的河渠水流问题的研究现状进展[C].中国水力2002年会议论文集.西安理工大学中国水利学会水力学专业委员会,2002年4月.
[27]王忖.有植被的河道水流试验研究[D].[硕士学位论文].江苏南京：河海大学,2003.
[28]毕慈芬,李桂芬,于倬德,等.砒砂岩地区植物“柔性坝”试验研究阶段总报[R].水利部黄委会上中游管理局,1999.
[29]拾兵,曹叔尤.植物治沙动力学[M].青岛：青岛海洋大学出版社,2000,11.
[30]拾兵.植物治沙力学机理及河宽动力调整研究[D].[博士学位论文].四川成都：四川大学,1998.
[31]M Fathi-Maghadam and N Kouwen. Nonrigid Nonsubmerged Vegetative Roughness on Floodplains. J. Hydr. Engrg., ASCE,1997,123(1):51-57.
[32]邱秀云,阿不都外力,程艳,等.植物“柔性坝”对水流影响的试验研究[J].水利水电技术,2003,34(9)：62-65.
[33]程艳.植物“柔性坝”水流特性的试验研究[D].[硕士学位论文].新疆乌鲁木齐：新疆农业大学,2004.
[34]阎洁,周著,邱秀云,等.植物“柔性坝”阻水试验及固沙机理分析[J].新疆农业大学学报,2004,27(3)：40-45.
[35]Naot D, Nezu I, Nakagawa H. Hydrodynamic Behavior of Partly Vegetated Open Channels [J]. J. Hydr. Engrg., ASCE,1996,122(11):625-663.
[36]Dan N, Iehisa Nezu I, Hiroji Nakagawa H. Unstable Pattern in Partly Vegetated Open Channels[J]. J. Hydr. Engrg., ASCE,1996,122(11):671-673.
[37]Fei-yong Chen. Turbulent Shear Flow in Shallow Open Channel with Training Structures [D].东京技术学院博士论文,日本东京,1996.
[38]Nadaoka K, Yagi H. Shallow-water Turbulence Modeling and Horizontal Large-eddy Computation of river flow[J]. J Hydraul Eng,1988,124(5).
[39]宿晓辉,张建新,李志伟,等.带有植物的河道水流浅水紊流运动大涡模拟[J].大连理工大学学报.2003,(2)：223-230.
[40]程莉.植物护岸条件下河道水流的数值模拟[D].[硕士学位论文].江苏南京：河海大学,2002.
[41]张二骏.流体数值模拟[J].河海大学科技情报,1990,11
[42]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,1989.
[43]谭维炎.计算浅水动力学—有限体积法的运用[M].北京：清华大学出版社,1998.
[44]M.G.Khublaryan,A.P Frolov,V N.Zyryanov. Modeling water flow in the presence of higher vegetation. Water Resources,2004,31 (6):617-622.
[45]章本照.流体力学中的有限元方法[M].北京：机械工业出版社,1986.
[46]苏铭德等.计算流体力学基础[M].北京：清华大学出版社,1989.
[47]马法三.计算流体力学—有限元法[M].南京：河海大学出版社,1989.
[48]W. H. Graf. Hydraulics of Sediment Transport [M]. MCGraw-Hill Book Company, New York,1973.
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