【摘要】：筒閥緊急動水關(guān)閉是保證水輪機(jī)安全運(yùn)行的保護(hù)措施之一，本文主要以水輪機(jī)全流道為模型，數(shù)值模擬筒閥動水關(guān)閉過程。以掌握水輪機(jī)運(yùn)行過程中筒閥及引流部件的水力特性、水輪機(jī)運(yùn)行狀況等為目的，利用FLUENT仿真軟件模擬筒閥60s動水關(guān)閉，研究筒閥動水關(guān)閉行程內(nèi)的壓力、速度、流量和力矩等水力特性變化規(guī)律，重點對小開度下的水力特性進(jìn)行細(xì)化分析。論文主要研究內(nèi)容和成果如下： (1)結(jié)合筒閥實際運(yùn)行工況，以轉(zhuǎn)輪轉(zhuǎn)速達(dá)到170r/min時的定常計算結(jié)果作為非定常計算的初始流場，依據(jù)筒閥實際關(guān)閉規(guī)律，利用profile定義筒閥關(guān)閉方式；對導(dǎo)葉和轉(zhuǎn)輪區(qū)域進(jìn)行網(wǎng)格加密，運(yùn)用滑移網(wǎng)格和動網(wǎng)格技術(shù)適應(yīng)流場區(qū)域變化，對不同套網(wǎng)格可信度進(jìn)行對比分析；以水輪機(jī)全流道網(wǎng)格為計算模型，選用用RNG k-湍流雙方程模型，采用SIMPLEC算法對流場進(jìn)行迭代求解，較真實的模擬筒閥動水關(guān)閉過程水輪機(jī)內(nèi)部流場特征。 (2)數(shù)值模擬得到筒閥動水關(guān)閉行程內(nèi)的上下端面、內(nèi)外表面的軸向動水作用力水力特性，并對其水力特性曲線進(jìn)行分析；筒閥周圍壓力和速度場不穩(wěn)定，筒閥在動水關(guān)閉過程中受到傾覆力矩作用，建立筒閥傾覆模型，并對筒閥傾覆穩(wěn)定性進(jìn)行評價，以判斷筒閥是否傾覆和卡死，為筒閥實際安全穩(wěn)定運(yùn)行提供參考依據(jù)。 (3)重點研究小開度下的水力特性，對小開度關(guān)閉行程再次進(jìn)行細(xì)化數(shù)值模擬，得到小開度下的筒閥過流區(qū)域流量和流速特性曲線；對筒閥下端面不同截面位置下不同點進(jìn)行取值，得到其在小開度下的變化規(guī)律；對筒閥附近區(qū)域、轉(zhuǎn)輪區(qū)域、環(huán)列平面葉柵導(dǎo)葉區(qū)域的壓力和速度場進(jìn)行分析，得到小開度下流場內(nèi)部的漩渦、脫流、尾跡流等不穩(wěn)定流和空化、汽蝕、振動等不穩(wěn)定現(xiàn)象。為筒閥運(yùn)行過程中的水力優(yōu)化提供參考，可與筒閥實際運(yùn)行工況進(jìn)行對比分析，采取相應(yīng)措施以使其運(yùn)行更高效、更穩(wěn)定。
[Abstract]:The emergency water closure of the cylinder valve is one of the protection measures to ensure the safe operation of the hydraulic turbine. This paper mainly uses the full flow path of the hydraulic turbine as a model to simulate the closing process of the cylinder valve, in order to master the hydraulic characteristics of the cylinder and drainage parts in the running process of the turbine and the running status of the hydraulic turbine, and use the FLUENT simulation software to simulate the cylinder valve 60s. When the water is closed, the hydraulic characteristics, such as pressure, velocity, flow and torque, are studied. The hydraulic characteristics of the small opening are detailed and analyzed. The main contents and results of this paper are as follows:
(1) according to the actual operating conditions of the cylinder valve, the constant calculation results of the rotary speed of 170r/min are taken as the initial flow field of unsteady calculation. According to the actual closing law of the cylinder valve, the closing mode of the cylinder valve is defined by profile, and the mesh of the guide vane and the rotary wheel is encrypt, and the slip grid and the dynamic grid technology are used to adapt the change of the flow field. The reliability of different sets of grid is compared and analyzed. Using the full flow path grid of hydraulic turbine as the calculation model, the RNG k- turbulent double equation model is selected and the SIMPLEC algorithm is used to solve the convection field iteratively. The flow characteristics of the turbine are simulated in a more real way.
(2) the hydraulic characteristics of the axial dynamic water force of the inner and outer surfaces of the cylinder valve are obtained by numerical simulation, and the hydraulic characteristics of the inner and outer surface are analyzed. The pressure and velocity field around the cylinder valve are not stable, and the tube valve is overturned by the overturning moment in the process of moving water closure, and the capsizing model of the cylinder valve is set up, and the overturning of the cylinder valve is stabilized. The evaluation is carried out to determine whether the cylinder valve is overturned and jammed, so as to provide reference for the safe and stable operation of the cylinder valve.
(3) focus on the hydraulic characteristics under the small opening, refine the small open stroke again, get the flow and velocity characteristic curve of the flow area under the small opening, get the value of the different points under the different section position of the lower end of the cylinder valve, and get the change law under the small opening. The pressure and velocity field in the region of the guide vane of the circular plane cascade are analyzed, and the instability of the vortex, defLOW, wake flow and other unstable flow and cavitation, cavitation, vibration, etc. in the flow field under the small opening is obtained, which provides a reference for the hydraulic optimization during the operation of the cylinder valve, and can be compared with the actual operating conditions of the cylinder valve. Measures are taken to make it more efficient and more stable.
【學(xué)位授予單位】：天津大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TK730

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 陳金霞;李國偉;劉勝柱;呂桂萍;;葉道渦產(chǎn)生機(jī)理及對水輪機(jī)穩(wěn)定性的影響[J];大電機(jī)技術(shù);2007年03期

2 王民富，，孔慶懷，趙越;水輪機(jī)圓筒閥的試驗研究[J];大電機(jī)技術(shù);1994年04期

3 白宏坤,李干生;抽水蓄能電站容量在電力系統(tǒng)中的合理比例[J];電力建設(shè);2001年06期

4 張思青,徐一民,王煜,張建蓉,沈東;筒閥技術(shù)特點及其應(yīng)用研究[J];閥門;2002年06期

5 王溥文,宗慕偉;昭平水電站船閘檻下分散輸水系統(tǒng)水力特性研究[J];廣西水利水電;1999年S1期

6 王祖卿;;淺談水輪發(fā)電機(jī)組的飛逸保護(hù)[J];湖北水力發(fā)電;2007年06期

7 張偉昊;劉火星;李維;鄒正平;;尾跡與渦輪葉柵邊界層的相互作用[J];航空動力學(xué)報;2009年04期

8 楊克昌;均質(zhì)圓柱類剛體對任意軸的轉(zhuǎn)動慣量計算公式[J];力學(xué)與實踐;1983年05期

9 劉洪波,韓平;閘門水力特性綜述[J];南水北調(diào)與水利科技;2005年02期

10 郝鑫;黃海艷;王海軍;樊晶晶;;高水頭平板閘門小開度的數(shù)值模擬與試驗對比[J];南水北調(diào)與水利科技;2012年01期

相關(guān)博士學(xué)位論文 前1條

1 郭春立;水輪機(jī)筒閥多缸協(xié)同關(guān)閉過程水力特性與控制策略研究[D];天津大學(xué);2009年

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