你的位置:水利论文 >> 论文 >> 江苏省 >> 江苏大学 >> 详细内容 在线投稿

低扬程大型泵站装置特性研究 【作者】陈松山 【导师】罗惕乾

热度53票 浏览89次 【共0条评论】【我要评论 时间:2007年7月01日 21:27

8RW6kDL0扬程大型泵站装置特性研究水利论文Y"wrE0W^\q

水利论文+s5kO+j;c)?qVJ4?]D

【作者】陈松山导师罗惕乾水利论文%X0sjzqDHLU}
【作者基本信息】江苏大学,流体机械及工程,2007年,博士水利论文],^ }U;c%B+T%m

,c"]%obE+m l0
QaQ G*B|bS*S(cG!i0【中文摘要】 本文研究以南水北调东线工程、城市防洪重点工程建设和大型泵站更新技术改造为背景。以低扬程大型泵站为研究对象,运用三维湍流数值模拟和实验研究相结合的方法,系统地研究了泵站工程过流构筑物中新型进水流道、出水流道内流场特性及水力特性,对比测试分析了常见流道的水力特性,提出了泵站新型进、出水流道型线参数确定的原则和方法。从理论上推演分析建立了泵装置动力特性预测数学模型;系统地研究了泵装置起动、停泵过渡过程,建立了完整的起动动态特性数学模型,提出了停泵动态特性计算方法。1.基于三维紊流数值模拟,以大型计算流体力学软件Fluent为平台,采用时均N-S方程(RANS)和κ-ε流模型,运用SIMPLEC算法,数值模拟了钟形、竖井贯流和簸箕形进水流道的内流场。以流道出口速度均匀度、速度加权平均角、水力损失大小为评价目标函数,研究了钟形进水流道不同喇叭口悬空高度的内流场特征和水力损失特性,提出了喇叭口悬空高度的合理取值范围。构建了钟形进水流道模型试验装置系统,利用五孔探针测试了不同喇叭口悬空高度时流道出口断面的流速分布,并与数值计算结果进行了比较分析,得出了带泵的流道出口速度分布规律。数值计算揭示了竖井贯...更多流、簸箕进水流道内流场特征、特征断面的流速及水力损失规律,并对竖井贯流泵装置特性、簸箕形进水流道水力特性进行了试验研究,提出了竖井贯流、簸箕形进水流道的优化特征型线及控制尺寸。2.运用三维湍流数值模拟的方法,对近年来应用于特低扬程大型泵站中的一种新型出水流道—箱涵式出水流道内流场特征及水力特性进行分析研究。研究中,针对喇叭出口设导水锥和不设导水锥,分别设计了不同喇叭口悬空高度、不同喇叭管型线、不同后壁距、不同后壁型线以及无扩散喇叭管等方案,数值模拟各方案流道内流场,预测旋涡发生位置和形态,得出了流道纵向剖面、喇叭口及出水柱状面上速度分布规律,预测并分析流道水力损失规律。构建模型试验装置系统,制作物理模型,对各数值计算方案进行系列试验研究,测得各方案流道的水力损失,观测了流道内水流流态,研究得出了流道水力损失随流道几何特征参数变化规律。根据数值计算和试验研究的结果,提出了新型箱涵式出水流道优化设计方法。对常见的虹吸式、直管式和钟形出水流道,设计并制作物理模型,测试并比较其水力损失。3.从流体力学基本原理出发,运用相似理论中的方程分析法,系统地分析泵装置动力特性、汽蚀特性、飞逸特性的相似模拟方法,阐述了相似准则之间的关系、参数换算比尺。从理论上分析和表达了水泵机械效率、水力效率、容积效率、水泵效率及泵装置效率。根据模型泵(或泵装置)试验数据,利用最小二乘法拟合及牛顿迭代法计算泵效率(或泵装置效率)表达式中拟合系数,将模型水泵各工况点效率分解为水力效率、容积效率和机械效率,实现了各部分效率按各自公式换算,提出了水力效率、容积效率、机械效率、管道效率、泵及泵装置效率换算的新方法,建立了低扬程大型泵站动力特性预测数学模型。4.在分析低扬程泵装置机组暂态电气特性、动力特性和管道中空气动力学特性基础上,结合水泵相似率,从理论上系统地研究了拍门断流直管式出流泵装置起动动态特性、虹吸式出水流道泵装置起动动态特性以及快速闸门断流直管式出流泵装置起动动态特性,并分别建立了相应的起动过渡过程数学模型。5.基于刚性水锤理论,分析和表达了低扬程大型泵装置水力特性和机组动力学特性,并运用最小二乘曲面拟合方法仿真模拟了水泵全性能曲线。为合理地在停泵动态特性计算中引入全特性曲线稳态参数,研究中,提出将水泵瞬态扬程分解为稳态扬程和惯性水头扬程,与之相应水阻力力矩、推力轴承摩擦力矩也分解为稳态力矩和惯性水头引起附加力矩,方程中稳态参数,即可用基于曲面拟合的全特性曲线方程代入,从而建立贯流泵站事故停泵、液压快速闸门断流停泵动态特性计算有限差分非线性方程组,并给出了计算方法、步骤和计算实例。  还原水利论文+bV,Vb%a

|+tLIU?%{9z0【英文摘要】 Based on the background for construction of East Route Project of the South-to-North Water Transfers, major project of city flood prevention and large pumping station reconstruction, this paper focuses on low-water head large scale pumping station. The internal flow pattern and hydraulic performances of new suction-boxes and discharge passages were systemically studied by applying three-turbulence numerical simulation technique and experimentation. The design criterion and methods were brought forward about how to determine reasonable outline and control parameters about new suction-box and outlet conduit. The hydraulic loss of three ordinary outlet conduits was also tested, compared and analyzed. The new property predication mathematical model of pump set performances were theoretically deduced and set up. This paper also systemically does research on transient process during starting period and pump stopping. The complete starting dynamic characteristic mathematical model and a group...更多 of new pump stopping dynamic characteristic equations were created. The main work and achievement details are as follows:1. The Reynolds-Averaged Navier-Stokes (RANS) equation was applied for the simulation of 3D flow field in bell-like, shaft tubular and dustpan shaped suction box of large pumping stations. The standard k-s turbulence model based on the Boussinesq hypothesis and SIMPLEC algorithm were adopted in the calculation. Velocity distribution uniformity, velocity-weighted average swirl angle and hydraulic loss magnitude were treated as value objective function during studying on internal pattern and hydraulic loss characteristics of bell-like intake conduit with different suction open heights. The optimization suction open height range was obtained. Constructing model apparatus system of bell-like suction box, the outlet section velocity distribution was measured by probe under various suction open heights. By comparing with computational results, the velocity distribution law of outlet section equipped with pump was revealed. According to the indicated internal flow pattern, velocity on special cross profile and hydraulic loss by numerical simulation and hydraulic characteristics by test, the optimum outline and "control dimensions about shaft tubular and dustpan shaped suction box were attained.2. Based on three-turbulence numerical simulation technique, the internal pattern and hydraulic characteristics were studied about new style outlet conduit namely called tank-like outlet passage which has been used in special low-water head city flood prevention pumping station for recent years. The different schemes of outlet open height, diffusion trumpet-like duct outline, the distance from back-wall to shaft center and no diffusion tube were designed with outlet cone or without outlet cone. By simulating each scheme internal flow field, the position and pattern of various types of vortices were predicted , the friction coefficient about various schemes are obtained and the law of hydraulic loss was also predicted and analyzed. Constructing model apparatus system and making physical models, each scheme hydraulic loss was measured and the variation law of hydraulic loss went with different geometry parameters came to light. According to numerical simulation and experimental results, the optimum design method about new style tank-like outlet conduit was put forward. The siphon discharge passage, straight outlet tube and bell-like outlet passage physical model were designed and made, three outlet passage hydraulic loss were measured and compared.3. Based on hydromechanics theory, the similitude methods for the model test of pump set characteristics, cavitation characteristics and runway speed characteristics were analyzed by applying the equation analytical method of analogy theory. The similarity criteria of parameters scaling laws and key points between the model experiments and the prototype experiments were set forth. The expressions of mechanical efficiency, hydraulic efficiency, cubage efficiency and overall efficiency for pump and pump set were given through theoretical analysis. Considering model pump or pump set experimental data, the constant coefficient used in the overall efficiency formula were obtained through least-square technique and Newton-Raphson method. From the view point of the new efficiency formula, the overall efficiency can be decomposed and each component should be converted alone between hydraulic model and prototype. According to analogy theory, the new conversion methods of mechanical efficiency, hydraulic efficiency, cubage efficiency, pump overall efficiency and pump set efficiency were put forward. The dynamical characteristics prediction mathematical model of low-water head pumping station was set up.4. Based on theoretical analysis of aerodynamic characteristics of the discharge pipeline, transient electric and dynamic characteristics of low-water head pump set, the transient parameters were systemically studied about straight discharge pipe with valve gate breaking flow, siphon outlet passage and straight discharge pipe with quick-stop gate breaking flow during starting period. The mathematical model of transient parameters was put forward for unsteady flow in low-water head pumping installation.5. Based on incompressible water hammer theory, the pump apparatus hydraulic characteristics and pump-unit dynamic characteristics were analyzed and expressed. By utilizing the mathematical model of least square surface fitting of a rectangular region and computer simulation technology, the universal complete pump characteristics was simulated. In order to introduce complete characteristics curves into computation, for the first time transient water head was decomposed into steady condition water head and inertia water head, accordingly water resistance moment and thrust bearing friction moment were also divided into steady condition moment and inertia additional moment. Finite-difference non-linear coupled equations of transient process were established in tubular pumping station while accidental pump-stopping happens or while pumping off with quick-stop gate breaking flow and Newton-Raphson iterative method was used to solve. The mathematical model was applied to simulate the transient process of actual pumping station of the east route of South-North Water Diversion Project during pump stopping.  还原水利论文v,T ["X2f8d

bm.A `vzbC0【中文关键词】 泵站; 进出水流道; 数值模拟; 试验研究; 相似换算; 特性预测; 动态特性
^&Y m&^3Is.z#Kt [b0【英文关键词】 pumping station; suction and outlet conduit; numerical simulation; experimental study; similarity conversion; performance prediction; transient characteristics
#d tj K*E2yY9bI0

q.e[pe-oW f0水利论文l)Y/Zz?1r*G]qt|r

 

5_o(Syg0
TAG: 泵站 特性 扬程 陈松山 罗惕乾
顶:4 踩:5
【已经有45人表态】
7票
极差
6票
很差
5票
较差
8票
稍差
4票
稍好
6票
较好
3票
很好
6票
极好
下一篇:隙控式全射流喷头理论及试验研究 【作者】李红 【导师】罗惕乾
上一篇:错列叶栅内部水动力学特性与汽液两相流动的研究 【作者】康灿 【导师】杨敏官
查看全部回复【已有0位网友发表了看法】

广告投放

广告投放