波浪影响下的海底泥沙再悬浮研究
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摘要
随着现代社会的发展,近岸海域环境污染越来越严重。于是底泥在海水水质问题中的重要作用,也越来越受到重视。然而,波浪作用下底泥运动的复杂性给水质控制和预报带来了极大的困难,随着计算机的迅速发展,以水动力学为基础的数值模拟为底泥运动与再悬浮研究提供了可能。
在假定海底泥沙水为牛顿流体的基础上,采用动量源法造波,末端设置人工衰减层消波,利用连续性方程和N-S方程模拟流体质点运动,采用VOF法追踪自由面和水-泥沙水的相界面运动,建立了空气—海水—高浓度泥沙水的数值波浪水槽,实现了波浪作用下泥沙水层内的动力学响应模拟。利用波谱分析手段,得到了表面波和内波的控制区域和作用情况,建立了表面波与内波波幅沿水深分布的解析表达式;在此基础上,考虑海底存在高浓度泥沙水层的实际情况,建立了修正起沙理论,推导了修正泥沙起动公式。
取得的主要成果为:随着水深加大,波动首先由表面波控制,逐渐过渡为由表面波和内波同时控制,最后由内波主要控制;表面波与内波在小幅值时,它们间的非线性相互作用可以忽略,可以独立的存在于水层和泥沙水层流场中;对于表面波和内波均可以采用有限水深的表面波解析公式计算,误差是可以忽略;对于表面波、内波场,波数的模拟值与解析解符合很好。波幅模拟值与解析解的趋势虽然一致,但存在一定误差;本文建立的波浪作用下泥沙起动公式与窦国仁的公式相比,本公式能够更好地反映泥沙起动过程。
最后,本文对泥沙再悬浮运动理论作了系统研究,建立了波浪作用下泥沙起动修正理论,得到了泥沙再悬浮条件,为近岸海底泥沙再悬浮预测提供了理论支持。
With the development of industry and agriculture, the pollution of marineenvironment is increasing seriously. The movement of sediment, which shows animportant role on seawater quality, attracts more and more attentions. The forecast andcontrol of seawater quality becomes very hard for the complex movement of sediment.As the development of computers, the numerical simulation of sediment movementbased on the hydrodynamics is becoming possible.
The wave is introduced by an oscillation momentum source and an artificialdamping layer is presented to absorb the reflection wave. The Navier-Stokes viscousflow theory is applied to simulate the movement fluids. The air-water surface andwater-sand water interface are tracked by VOF method. The control-volume-basedtechnique is used to convert the governing equations to algebraic equations that can besolved numerically. By comparing the theorical results, the correctness and thestability of our numerical wave tank is proved. With the FFT technique, the controlarea of surface wave and internal wave is outlined. The analytical equation of theamplitude distributation of surface wave and internal wave along the depth is found.Furthermore, the modified theory on sand resuspension is estabilished by consideringthe real existing high dense sand water.
The main results are: The surface water has strong influence on the movement ofwater-sand water interface. In reverse, the internal wave at interface has little effect onthe movement of air-water surface. With increasing the depth, the fluid movement isat first controlled by surface wave. Then it is controlled by surface wave and internalwave and finally it is controlled by internal wave mainly. When the amplitude ofsurface wave is small, the surface wave and internal wave are in linearity. Theanalytical equation of amplitude of surface wave and internal wave with respect to thedepth is comfirmed to be correct. The modified theory is comparied with that of DouGuoren, it is found the new theory is more reasonable to reflect the details of sandresuspension process.
In the end, the systemic investigation of sand resuspension process caused bysurface wave is carried out in present research. The sand resuspension theory isestabilished and the resuspension condition is given out. The outcomes provide an predictable theory for seabed sand resuspension.
在假定海底泥沙水为牛顿流体的基础上,采用动量源法造波,末端设置人工衰减层消波,利用连续性方程和N-S方程模拟流体质点运动,采用VOF法追踪自由面和水-泥沙水的相界面运动,建立了空气—海水—高浓度泥沙水的数值波浪水槽,实现了波浪作用下泥沙水层内的动力学响应模拟。利用波谱分析手段,得到了表面波和内波的控制区域和作用情况,建立了表面波与内波波幅沿水深分布的解析表达式;在此基础上,考虑海底存在高浓度泥沙水层的实际情况,建立了修正起沙理论,推导了修正泥沙起动公式。
取得的主要成果为:随着水深加大,波动首先由表面波控制,逐渐过渡为由表面波和内波同时控制,最后由内波主要控制;表面波与内波在小幅值时,它们间的非线性相互作用可以忽略,可以独立的存在于水层和泥沙水层流场中;对于表面波和内波均可以采用有限水深的表面波解析公式计算,误差是可以忽略;对于表面波、内波场,波数的模拟值与解析解符合很好。波幅模拟值与解析解的趋势虽然一致,但存在一定误差;本文建立的波浪作用下泥沙起动公式与窦国仁的公式相比,本公式能够更好地反映泥沙起动过程。
最后,本文对泥沙再悬浮运动理论作了系统研究,建立了波浪作用下泥沙起动修正理论,得到了泥沙再悬浮条件,为近岸海底泥沙再悬浮预测提供了理论支持。
With the development of industry and agriculture, the pollution of marineenvironment is increasing seriously. The movement of sediment, which shows animportant role on seawater quality, attracts more and more attentions. The forecast andcontrol of seawater quality becomes very hard for the complex movement of sediment.As the development of computers, the numerical simulation of sediment movementbased on the hydrodynamics is becoming possible.
The wave is introduced by an oscillation momentum source and an artificialdamping layer is presented to absorb the reflection wave. The Navier-Stokes viscousflow theory is applied to simulate the movement fluids. The air-water surface andwater-sand water interface are tracked by VOF method. The control-volume-basedtechnique is used to convert the governing equations to algebraic equations that can besolved numerically. By comparing the theorical results, the correctness and thestability of our numerical wave tank is proved. With the FFT technique, the controlarea of surface wave and internal wave is outlined. The analytical equation of theamplitude distributation of surface wave and internal wave along the depth is found.Furthermore, the modified theory on sand resuspension is estabilished by consideringthe real existing high dense sand water.
The main results are: The surface water has strong influence on the movement ofwater-sand water interface. In reverse, the internal wave at interface has little effect onthe movement of air-water surface. With increasing the depth, the fluid movement isat first controlled by surface wave. Then it is controlled by surface wave and internalwave and finally it is controlled by internal wave mainly. When the amplitude ofsurface wave is small, the surface wave and internal wave are in linearity. Theanalytical equation of amplitude of surface wave and internal wave with respect to thedepth is comfirmed to be correct. The modified theory is comparied with that of DouGuoren, it is found the new theory is more reasonable to reflect the details of sandresuspension process.
In the end, the systemic investigation of sand resuspension process caused bysurface wave is carried out in present research. The sand resuspension theory isestabilished and the resuspension condition is given out. The outcomes provide an predictable theory for seabed sand resuspension.
引文
[1]董胜,孔令双.海洋工程环境概论[M].青岛:中国海洋大学出版社, 2005,191-193.
[2]贺松林.海岸工程与环境概论[M].北京:海洋出版社,2003,1-4.
[3]胡克林,丁平兴,朱首贤,等.长江口附近海域台风浪的数值模拟—以鹿沙台风和森拉克台风为例[J].海洋学报,2004,26(5):23-33.
[4]蒋智勇,程和琴,陈吉余,等.长江口南槽底沙再悬浮对重金属吸附的影响[J].安全与环境学报,2003,3(3):36-40.
[5]陈沈良,张国安,杨世伦,等.长江口水域悬沙浓度时空变化与泥沙再悬浮[J].地理学报,2004,59(2):260-266.
[6]王丕波,宋金明,郭占勇,等.海洋表层沉积物再悬浮的诱因及其对生源要素循环的影响[J].海洋学报,2005,29(10):77-80.
[7]罗潋葱,秦伯强.太湖波浪与湖流对沉积物再悬浮不同影响的研究[J].水文,2003,23(3):1-4.
[8]车越,何青,吴阿娜.河口泥沙再悬浮对悬沙中重金属元素的影响[J].长江流域资源与环境,2003,12(5):40-44.
[9]钱嫦萍,陈振楼,胡玲珍,等.崇明东滩沉积物再悬浮对水界面氮、磷交换行为的影响[J].环境科学,2003,24(5):114-119.
[10]郭玲.天然水体中颗粒悬浮物对有机污染水体系净化的实验模拟[J].蒙自师专学报,1997,14(4):20-23.
[11]禹雪中,钟德钰,李锦秀,等.水环境中泥沙作用研究进展及分析[J]. 2004,(6):75-80.
[12]陈聚法,赵俊,孙耀桑,等.沟湾贝类养殖水域沉积物再悬浮的动力机制及其对水体中营养盐的影响[J].海洋水产研究,2007,28(3):105-111.
[13]钱宁,万兆惠.泥沙运动力学[M].北京:科学出版社,1983,10-12.
[14]Hasselmann K. On the spectral dissipation of ocean waves due to whitecapping[J].Boundary-LayerMeteorology,1974,6(1-2):107-127.
[15]曹文洪,刘青泉.波浪掀沙的动力学机理分析[J].水利学报,2000,(1):49-59.
[16]杨美卿,王桂玲.粘性细泥沙的临界起动公式[J].应用基础与工程科学学报,1995,3(1):99-109.
[17]蒋昌波,白玉川,姜乃申,等.海河口粘性淤泥起动规律研究[J].水利学报,2001,(6):51-56.
[18]赵子丹.波浪边界层和底沙起动[J].港口工程,1987,(1):25-30.
[19]刘青泉,曹文洪.泥沙颗粒的扬动机理分析[J].水利学报,1998,(5):1-6.
[20]陆永军,左利钦,王红川,等.波浪与潮流共同作用下二维泥沙数学模型[J].泥沙研究,2005,(6):1-12.
[21]马进荣,罗肇森,张晓艳.有浮泥水域的平面二维泥沙数学模型研究[J].泥沙研究,2008,(5):49-53.
[22]唐存本.泥沙起动规律[J].水利学报,1963,4(2):1-12.
[23]韩其为.泥沙起动规律及起动流速[J].泥沙研究,1982,6(2):11-26.
[24]韩其为,何明民.细颗粒泥沙成团起动及其流速的研究[J].湖泊科学, 1997,9(4):307-316.
[25]张兰丁.粘性泥沙起动流速的探讨[J].水动力学研究与进展, 2000, 15(1):82-88.
[26]窦国仁.再论泥沙起动流速[J].泥沙研究,1999,(6):1-9.
[27]窦国仁,窦希萍,李提来.波浪作用下泥沙的起动规律[J].中国科学, 2001,31(6):566-573.
[28]窦国仁,董凤舞,窦希萍.河口海岸泥沙数学模型研究[J].中国科学, 1995,25(9):995-1001.
[29]窦国仁.河口海岸全沙模型相似理论[J].水利水运工程学报,2001,(1):1-12.
[30]Dou Guoren. On the theory incipient motion of sediment particles[J]. ScientiaSinica,1962,11(7):999-1032.
[31]金德春.关于泥沙的起动问题[J].泥沙研究,1991,6(2):79-83.
[32]周益人,尹畅安.波浪边界层下的泥沙起动[J].泥沙研究,2004,(1):15-22..
[33]黄明政,赵冲久.粉砂的起动规律研究[J].水道港口,2004,25(3):135-139.
[34]王光谦,胡春宏.泥沙研究进展[M].北京:中国水利水电出版社,2006.
[35]肖厚蓬.波浪影响下海洋底泥的水动力学数值模拟[D].天津:天津大学环境学院,2007.
[36]杨宁.非均匀气固两相流动的计算机模拟—多尺度方法与双流体模型的结合[D].北京:中国科学院过程工程研究所,2003.
[37]Nguyen T. Radiation-diffraction problem with forward speed in a two-layerfiuid[C]. 14th international workshop on water waves and floating bodies, April1999.
[38]陈怀珲.MATLAB及其在理工课程中的应用指南[M].西安:西安电子科技大学出版社,2004.
[39]Copeland G J M. A practiacal alternative to the mild-slope wave equation[J].Coastal Engineering,1985,(9):125-149.
[40]Hit C W, Nichols B D. Volume of Fluid (VOF) method for the dynamics of freeboundaries[J].JournalofComputationalPhysics,1981,(39):201-225.
[41]张殿新.数值波浪水槽(水池)的前后处理研究[D].天津:天津大学机械工程学院,2006.
[42]Lin P Z, Liu P L F. Internal wave-maker for Navier-Stokes equations models[J].Journal of Waterway, Port, Coastal, and Ocean Engineering, 1999, 125(4):207-215.
[43]周勤俊,王本龙,兰雅梅,等.海堤越浪的数值模拟[J].力学季刊, 2005,26(4):629-633.
[44]BullockGN,MurtonGJ.Performanceofawedgetypeabsorbingwavemaker[J].Journal of Waterway, Port, Coastal, and Ocean Engineering, 1999, 125(4):207-215.
[45]Wang Y X. Numerical wave channel with absorbing wave maker[J]. Journal ofHydrodynamics (A),1994,9(2):204-205.
[46]孙大鹏,李玉成.数值水槽内的阻尼消波和波浪变形计算[J].海洋工程, 2000,18(2):46-50.
[47]Larsen J, Dancy H. Open boundaries in short wave simulations-a newapproach[J].CoastalEngineering,1983,(7):285-297.
[48]严恺.海岸工程[M].北京:海洋出版社,2002,207-614.
[49]Dou Guoren. On the theory of incipient motion of sediment particles[J]. ScientiaSinica, 1962,11(7):999-1032.
[50]万兆惠,宋天成.水压力对细颗粒泥沙起动流速影响的试验研究[J].泥沙研究,1990,(4):62-69.
[2]贺松林.海岸工程与环境概论[M].北京:海洋出版社,2003,1-4.
[3]胡克林,丁平兴,朱首贤,等.长江口附近海域台风浪的数值模拟—以鹿沙台风和森拉克台风为例[J].海洋学报,2004,26(5):23-33.
[4]蒋智勇,程和琴,陈吉余,等.长江口南槽底沙再悬浮对重金属吸附的影响[J].安全与环境学报,2003,3(3):36-40.
[5]陈沈良,张国安,杨世伦,等.长江口水域悬沙浓度时空变化与泥沙再悬浮[J].地理学报,2004,59(2):260-266.
[6]王丕波,宋金明,郭占勇,等.海洋表层沉积物再悬浮的诱因及其对生源要素循环的影响[J].海洋学报,2005,29(10):77-80.
[7]罗潋葱,秦伯强.太湖波浪与湖流对沉积物再悬浮不同影响的研究[J].水文,2003,23(3):1-4.
[8]车越,何青,吴阿娜.河口泥沙再悬浮对悬沙中重金属元素的影响[J].长江流域资源与环境,2003,12(5):40-44.
[9]钱嫦萍,陈振楼,胡玲珍,等.崇明东滩沉积物再悬浮对水界面氮、磷交换行为的影响[J].环境科学,2003,24(5):114-119.
[10]郭玲.天然水体中颗粒悬浮物对有机污染水体系净化的实验模拟[J].蒙自师专学报,1997,14(4):20-23.
[11]禹雪中,钟德钰,李锦秀,等.水环境中泥沙作用研究进展及分析[J]. 2004,(6):75-80.
[12]陈聚法,赵俊,孙耀桑,等.沟湾贝类养殖水域沉积物再悬浮的动力机制及其对水体中营养盐的影响[J].海洋水产研究,2007,28(3):105-111.
[13]钱宁,万兆惠.泥沙运动力学[M].北京:科学出版社,1983,10-12.
[14]Hasselmann K. On the spectral dissipation of ocean waves due to whitecapping[J].Boundary-LayerMeteorology,1974,6(1-2):107-127.
[15]曹文洪,刘青泉.波浪掀沙的动力学机理分析[J].水利学报,2000,(1):49-59.
[16]杨美卿,王桂玲.粘性细泥沙的临界起动公式[J].应用基础与工程科学学报,1995,3(1):99-109.
[17]蒋昌波,白玉川,姜乃申,等.海河口粘性淤泥起动规律研究[J].水利学报,2001,(6):51-56.
[18]赵子丹.波浪边界层和底沙起动[J].港口工程,1987,(1):25-30.
[19]刘青泉,曹文洪.泥沙颗粒的扬动机理分析[J].水利学报,1998,(5):1-6.
[20]陆永军,左利钦,王红川,等.波浪与潮流共同作用下二维泥沙数学模型[J].泥沙研究,2005,(6):1-12.
[21]马进荣,罗肇森,张晓艳.有浮泥水域的平面二维泥沙数学模型研究[J].泥沙研究,2008,(5):49-53.
[22]唐存本.泥沙起动规律[J].水利学报,1963,4(2):1-12.
[23]韩其为.泥沙起动规律及起动流速[J].泥沙研究,1982,6(2):11-26.
[24]韩其为,何明民.细颗粒泥沙成团起动及其流速的研究[J].湖泊科学, 1997,9(4):307-316.
[25]张兰丁.粘性泥沙起动流速的探讨[J].水动力学研究与进展, 2000, 15(1):82-88.
[26]窦国仁.再论泥沙起动流速[J].泥沙研究,1999,(6):1-9.
[27]窦国仁,窦希萍,李提来.波浪作用下泥沙的起动规律[J].中国科学, 2001,31(6):566-573.
[28]窦国仁,董凤舞,窦希萍.河口海岸泥沙数学模型研究[J].中国科学, 1995,25(9):995-1001.
[29]窦国仁.河口海岸全沙模型相似理论[J].水利水运工程学报,2001,(1):1-12.
[30]Dou Guoren. On the theory incipient motion of sediment particles[J]. ScientiaSinica,1962,11(7):999-1032.
[31]金德春.关于泥沙的起动问题[J].泥沙研究,1991,6(2):79-83.
[32]周益人,尹畅安.波浪边界层下的泥沙起动[J].泥沙研究,2004,(1):15-22..
[33]黄明政,赵冲久.粉砂的起动规律研究[J].水道港口,2004,25(3):135-139.
[34]王光谦,胡春宏.泥沙研究进展[M].北京:中国水利水电出版社,2006.
[35]肖厚蓬.波浪影响下海洋底泥的水动力学数值模拟[D].天津:天津大学环境学院,2007.
[36]杨宁.非均匀气固两相流动的计算机模拟—多尺度方法与双流体模型的结合[D].北京:中国科学院过程工程研究所,2003.
[37]Nguyen T. Radiation-diffraction problem with forward speed in a two-layerfiuid[C]. 14th international workshop on water waves and floating bodies, April1999.
[38]陈怀珲.MATLAB及其在理工课程中的应用指南[M].西安:西安电子科技大学出版社,2004.
[39]Copeland G J M. A practiacal alternative to the mild-slope wave equation[J].Coastal Engineering,1985,(9):125-149.
[40]Hit C W, Nichols B D. Volume of Fluid (VOF) method for the dynamics of freeboundaries[J].JournalofComputationalPhysics,1981,(39):201-225.
[41]张殿新.数值波浪水槽(水池)的前后处理研究[D].天津:天津大学机械工程学院,2006.
[42]Lin P Z, Liu P L F. Internal wave-maker for Navier-Stokes equations models[J].Journal of Waterway, Port, Coastal, and Ocean Engineering, 1999, 125(4):207-215.
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