管道动力系统即时瞬变与延时瞬变特性研究
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摘要
在许多行业的流体动力系统中，瞬变现象时有发生，全面探索整个系统的瞬变特性，找出其发生强瞬变的内在原因，提出防止和控制手段，是当前面临的重要课题。据此，本文在动力系统综合实验装置上对不同上游水位、运行流量、以及不同的运行管长进行了可调节与非调节工况的实验模拟，通过实验研究和理论分析，提出了瞬变强度系数与容性因子与惯性因子比的概念，主要内容和结论如下：不同流量和上游压头的组合情况下，系统表现出不同的瞬变特性，即而可将瞬变工况大致分为两类：强瞬变和弱瞬变，而瞬变强度可用瞬变强度系数来表示。是否发生强瞬变由系统内在因素决定，即h_0／q(v0)比值决定，比值越小发生瞬变的强度越大，而非调节工况的发生起到了诱导和催化作用。具有较大容积的液体容器具有容性特性，而管系内的运动流体具有惯性特性。本文中上游水箱水位可作为容性因子，管系内流量可作为惯性因子。而h0／q_(v0)代表了容性因子与惯性因子比值，它决定了系统的瞬变强度。实验研究和分析发现，从发生瞬变的时间来说，在非调节工况发生的同时和经过一段较短的时间，要出现两次强度不同的瞬变，本文称为即时瞬变与延时瞬变，这一新的研究成果，将会深化瞬变特性研究，拓展瞬变特性理论，具有学术意义和实际应用价值。本文还为减小瞬变强度和应继续研究的问题提供了方向。
In the fluid dynamic systems of many industries, transient phenomena may occur frequently. So, presently, it is an important task to explore transient properties of the whole systems, find out the reasons that make the transient occur, presenting methods to prevent and control it. Hereby, this paper made experimental imitation in both adjustable and no adjustable operating modes, during which different water levels in the upper reaches, operation flow, and operation lengths in the experimental device were given. After having made experimental researches and theoretical analyses, this paper presented the concepts of transient intensity and the ration of volume factor to inertia factor. The main contents and conclusions are: the systems show the different transient properties when the different flow and pressures in the upper reaches are set. And that, the transient operating mode can be classified as two kinds: strong transient and weak transient. Transient intensity can be denoted by transient intensity coef
ficient. The inside factor, that is the ratio of ho to qv0 in the systems, is decisive to make the strong transient occur. Moreover, the smaller the ratio, the more intense the transient will be, in which the adjustable operating mode plays an inductive role. The fluid in a great container possesses property; the moving fluid in
pipes possesses an inertia property insteadly. In this paper, water level in the upper tank can be seen as capacitive factor, flow in the pipes can be seen as an inertia factor. Furthermore h0/qv0 denotes the ratio of capacitive factor to inertia factor, and it determines the transient intensity. From the experimental researches and analyses, we found that the transient will occur twice at the same time and after a period of time when the no adjustable operating mode occurs, each of which has a different intensity. We name them as simultaneous transient and delayed transient respectively. This new research results will deepen the study on the transient properties and develop the theory of the transient properties. So it possesses science meaning and factual application value. Furthermore, this paper also point out a direction in reducing the transient intensity and those problems which should be studied fatherly.
In the fluid dynamic systems of many industries, transient phenomena may occur frequently. So, presently, it is an important task to explore transient properties of the whole systems, find out the reasons that make the transient occur, presenting methods to prevent and control it. Hereby, this paper made experimental imitation in both adjustable and no adjustable operating modes, during which different water levels in the upper reaches, operation flow, and operation lengths in the experimental device were given. After having made experimental researches and theoretical analyses, this paper presented the concepts of transient intensity and the ration of volume factor to inertia factor. The main contents and conclusions are: the systems show the different transient properties when the different flow and pressures in the upper reaches are set. And that, the transient operating mode can be classified as two kinds: strong transient and weak transient. Transient intensity can be denoted by transient intensity coef
ficient. The inside factor, that is the ratio of ho to qv0 in the systems, is decisive to make the strong transient occur. Moreover, the smaller the ratio, the more intense the transient will be, in which the adjustable operating mode plays an inductive role. The fluid in a great container possesses property; the moving fluid in
pipes possesses an inertia property insteadly. In this paper, water level in the upper tank can be seen as capacitive factor, flow in the pipes can be seen as an inertia factor. Furthermore h0/qv0 denotes the ratio of capacitive factor to inertia factor, and it determines the transient intensity. From the experimental researches and analyses, we found that the transient will occur twice at the same time and after a period of time when the no adjustable operating mode occurs, each of which has a different intensity. We name them as simultaneous transient and delayed transient respectively. This new research results will deepen the study on the transient properties and develop the theory of the transient properties. So it possesses science meaning and factual application value. Furthermore, this paper also point out a direction in reducing the transient intensity and those problems which should be studied fatherly.
引文
[1] [美]E．B怀利，V．L斯特里特．瞬变流，水利电力出版社．
[2] 董若凌．动力失灵与系统断流工况动力系统空穴特性研究与计算，太原理工大学硕士学位论文，2002．3．
[3] 郑铭．两相流瞬变流动的计算方法和实验研究，江苏理工大学学报，1999，Nol，475～578．
[4] 李欣等．串联泵组的瞬变工况，第十四届全国水动力学研讨会文集，2000，贵阳，北京：海洋出版社，2000：162～165．
[5] 刘云芳等．系统中容性装置对泵组瞬变特性的影响，第十五届全国水动力学研讨会文集，2001，武汉，北京：海洋出版社，2001：446～450．
[6] 于永海．有压瞬变流反问题研究，水利水电科技进展，Vol 20，No 5，2002，
[7] Anderson A, Menabrea's Note on Waterhammer,1958, ASCE Journal of the Hydraulics Division, 1976,102(HY1).
[8] Evangelisti G,Waterhammer Analysis by the Method of Characteristics, LiEnerg. Elec, VolXLVI, No10,11, Milan, 1969
[9] Marchal M G Flesh and P Surer, The calculation of Waterhammer Problems by Means of the Digital Computer, Proc.int. symp. waterhammer pumped storage projects, ASME,Chicago, Nov.1965.
[10] Seeter V Land E B Wylie, Transient Analysis of Offshore Loading System, J. of Eng. For Industry, Trans, ASME, Vol 97, Sec. B, No 1, Feb. 1975.
[11] Tijsseling A S, Vardy AE&Fan D,Fluid Structure Interation in a T-pipe, Journal of Fluids and Structure, 1996,10.
[12] Tijsseling A S,Vardy AE&Fan D,Fluid Structure Interation and Caviation in a Single-elbow Pipe System,Journal of Fluids and Structure, 1996, 10.
[13] Lavooij C S W&Tijsseling A S,Fluid-structure Interraction Liquid-filled Piping Systems,Journal of fluids and Structure, 1991, 5.
[14] Kruisbrink A C H&Heinxbroek A G JFluid-steucture Interation in Non-rigid Pipeline Systems-large Scale Validation Test, Proc. of the Int. Louf.on Pipelion Systems, BHRG, Manchester, March, 1992.
[15] Kawaguchi,Applications of interferometric laser imaging technique to the spatial analysis on a transient spray flow, Nippon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B, v 68, n 666, February, 2002, p 576-583
[16] Walter F,Computation of energy dissipation in transient flow,Journal of Hydraulic Engineering,v 123, n 2, Feb, 1997, p 108-115
[17] Prasser.H,Measurement techniques for steady and transient multiphase flows, Kerntechnik, v 68, n 3, May, 2003, p 77
[18] Inada.S,Transient thermal mixing performance and flow pattern in a room with through-flow, Journal of Flow Visualization and Image Processing, v 9, n 2-3, 2002, p 229-245
[19] Van Der Linden, R.J, Transients in flow and local heat transfer due to a pressure wave in pipe flow, Applied Scientific Research (The Hague), v 52, n 4, June, 1994, p 371-399
[20] Marduel,.X, Suboptimal control of transient nonisothermal viscoelastic fluid flows, Physics of Fluids, v 13, n 9, September, 2001, p 2478-2491
[21] 杨建设．瞬变流动中水力摩损的影响研究，水利学报，1999．No．2．
[22] 蒋劲，刘光临等．气穴瞬变基本方程特征根问题研究，华中理工大学学报，Vol 25，No 8，1997，8．
[23] 于永海等．有压瞬变流反向问题研究综述，水利水电科技进展，Vol 20，No 5．2000，10．
[24] 郜振华．水电站瞬变流计算方法研究及计算程序开发，河海大学硕士学位论文，2002，5．
[25] 马素霞，阎庆绂等．截留在管道中气体引起的瞬变流动，第十三届全国水动力学研究与进展研讨会，贵阳，1999，10．
[26] Ma Su Xia, Li Xin,Yan QingFu,Transient Characteristics of Condensate System of a Power Plant, ACFM-8 December 6-10,1999, Shen Zhen, China.
[27] 靳思宇．阀调节泵系统特性研究与计算，太原理工大学硕士学位论文，2002，3．
[28] 李欣．火电厂凝结水系统瞬变工况特性研究，太原理工大学硕士学位论文，2001，3．
[29] 刘云芳．动力系统失控工况特性及预防控制研究，太原理工大学硕士学位论文，2003，3．
[30] 郑体宽．热力发电厂，北京：中国电力出版社，1997．
[31] 郭立君．泵与风机，北京：中国电力出版社，1986．
[32] 吴望一．流体力学，北京大学出版社，1983．
[33] 孔珑．工程流体力学，中国电力出版社，1995．
[34] 吴持恭．水力学，高等教育出版社，1998．
[35] 陈材侃．计算流体力学，重庆出版社，1992．
[36] 苏铭德等．计算流体力学基础，清华大学出版社，1997．
[37] 孙祥海等．计算流体力学导论，上海交通大学出版社，1987．
[2] 董若凌．动力失灵与系统断流工况动力系统空穴特性研究与计算，太原理工大学硕士学位论文，2002．3．
[3] 郑铭．两相流瞬变流动的计算方法和实验研究，江苏理工大学学报，1999，Nol，475～578．
[4] 李欣等．串联泵组的瞬变工况，第十四届全国水动力学研讨会文集，2000，贵阳，北京：海洋出版社，2000：162～165．
[5] 刘云芳等．系统中容性装置对泵组瞬变特性的影响，第十五届全国水动力学研讨会文集，2001，武汉，北京：海洋出版社，2001：446～450．
[6] 于永海．有压瞬变流反问题研究，水利水电科技进展，Vol 20，No 5，2002，
[7] Anderson A, Menabrea's Note on Waterhammer,1958, ASCE Journal of the Hydraulics Division, 1976,102(HY1).
[8] Evangelisti G,Waterhammer Analysis by the Method of Characteristics, LiEnerg. Elec, VolXLVI, No10,11, Milan, 1969
[9] Marchal M G Flesh and P Surer, The calculation of Waterhammer Problems by Means of the Digital Computer, Proc.int. symp. waterhammer pumped storage projects, ASME,Chicago, Nov.1965.
[10] Seeter V Land E B Wylie, Transient Analysis of Offshore Loading System, J. of Eng. For Industry, Trans, ASME, Vol 97, Sec. B, No 1, Feb. 1975.
[11] Tijsseling A S, Vardy AE&Fan D,Fluid Structure Interation in a T-pipe, Journal of Fluids and Structure, 1996,10.
[12] Tijsseling A S,Vardy AE&Fan D,Fluid Structure Interation and Caviation in a Single-elbow Pipe System,Journal of Fluids and Structure, 1996, 10.
[13] Lavooij C S W&Tijsseling A S,Fluid-structure Interraction Liquid-filled Piping Systems,Journal of fluids and Structure, 1991, 5.
[14] Kruisbrink A C H&Heinxbroek A G JFluid-steucture Interation in Non-rigid Pipeline Systems-large Scale Validation Test, Proc. of the Int. Louf.on Pipelion Systems, BHRG, Manchester, March, 1992.
[15] Kawaguchi,Applications of interferometric laser imaging technique to the spatial analysis on a transient spray flow, Nippon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B, v 68, n 666, February, 2002, p 576-583
[16] Walter F,Computation of energy dissipation in transient flow,Journal of Hydraulic Engineering,v 123, n 2, Feb, 1997, p 108-115
[17] Prasser.H,Measurement techniques for steady and transient multiphase flows, Kerntechnik, v 68, n 3, May, 2003, p 77
[18] Inada.S,Transient thermal mixing performance and flow pattern in a room with through-flow, Journal of Flow Visualization and Image Processing, v 9, n 2-3, 2002, p 229-245
[19] Van Der Linden, R.J, Transients in flow and local heat transfer due to a pressure wave in pipe flow, Applied Scientific Research (The Hague), v 52, n 4, June, 1994, p 371-399
[20] Marduel,.X, Suboptimal control of transient nonisothermal viscoelastic fluid flows, Physics of Fluids, v 13, n 9, September, 2001, p 2478-2491
[21] 杨建设．瞬变流动中水力摩损的影响研究，水利学报，1999．No．2．
[22] 蒋劲，刘光临等．气穴瞬变基本方程特征根问题研究，华中理工大学学报，Vol 25，No 8，1997，8．
[23] 于永海等．有压瞬变流反向问题研究综述，水利水电科技进展，Vol 20，No 5．2000，10．
[24] 郜振华．水电站瞬变流计算方法研究及计算程序开发，河海大学硕士学位论文，2002，5．
[25] 马素霞，阎庆绂等．截留在管道中气体引起的瞬变流动，第十三届全国水动力学研究与进展研讨会，贵阳，1999，10．
[26] Ma Su Xia, Li Xin,Yan QingFu,Transient Characteristics of Condensate System of a Power Plant, ACFM-8 December 6-10,1999, Shen Zhen, China.
[27] 靳思宇．阀调节泵系统特性研究与计算，太原理工大学硕士学位论文，2002，3．
[28] 李欣．火电厂凝结水系统瞬变工况特性研究，太原理工大学硕士学位论文，2001，3．
[29] 刘云芳．动力系统失控工况特性及预防控制研究，太原理工大学硕士学位论文，2003，3．
[30] 郑体宽．热力发电厂，北京：中国电力出版社，1997．
[31] 郭立君．泵与风机，北京：中国电力出版社，1986．
[32] 吴望一．流体力学，北京大学出版社，1983．
[33] 孔珑．工程流体力学，中国电力出版社，1995．
[34] 吴持恭．水力学，高等教育出版社，1998．
[35] 陈材侃．计算流体力学，重庆出版社，1992．
[36] 苏铭德等．计算流体力学基础，清华大学出版社，1997．
[37] 孙祥海等．计算流体力学导论，上海交通大学出版社，1987．