【摘要】：近年來(lái),隨著水輪機(jī)組單機(jī)容量及轉(zhuǎn)輪直徑的不斷增大,電站已經(jīng)不再片面追求高效率,而是把運(yùn)行穩(wěn)定性放在首位。圓筒閥作為一種新型的進(jìn)水閥,它是安裝在水輪機(jī)的固定導(dǎo)葉和活動(dòng)導(dǎo)葉之間,它能夠起到止水閥的作用,可以阻止水流通過(guò)活動(dòng)導(dǎo)葉,對(duì)于泥沙含量高的電站,在機(jī)組停機(jī)時(shí),能夠很好的保護(hù)導(dǎo)水機(jī)構(gòu),避免由于間隙空化和泥沙磨損造成的導(dǎo)葉漏水量過(guò)大。此外,當(dāng)機(jī)組事故甩負(fù)荷時(shí),如果調(diào)速器失靈,機(jī)組發(fā)生飛逸,圓筒閥是可以動(dòng)水關(guān)閉的,避免了水輪發(fā)電機(jī)組長(zhǎng)時(shí)間的處于飛逸狀態(tài),從而保護(hù)了機(jī)組的安全。因此對(duì)混流式水輪機(jī)圓筒閥進(jìn)行研究十分必要。論文以某個(gè)投標(biāo)項(xiàng)目為例,應(yīng)用商業(yè)CFD軟件CFX14.0對(duì)水輪機(jī)全流道的三維流動(dòng)進(jìn)行了數(shù)值計(jì)算,通過(guò)CFD數(shù)值模擬獲得了在不同水頭和流速下圓筒閥所體現(xiàn)的水力特性,并由此得到特定水頭和流速范圍下圓筒閥的最優(yōu)幾何外形;對(duì)機(jī)械液壓控制裝置的研究開(kāi)發(fā);對(duì)圓筒閥本身和水輪機(jī)頂蓋、座環(huán)等部件的相關(guān)結(jié)構(gòu)進(jìn)行了研究,結(jié)合圓筒閥筒體的導(dǎo)向結(jié)構(gòu)、筒體的剛強(qiáng)度及屈曲分析、筒體固有振動(dòng)頻率等方面確定筒體的結(jié)構(gòu)尺寸。已經(jīng)能夠運(yùn)用CFD分析計(jì)算圓筒閥在關(guān)閉過(guò)程中流道內(nèi)速度場(chǎng)、壓力場(chǎng)的變化情況、圓筒閥閥體內(nèi)外表面的壓力特性以及周?chē)鲌?chǎng)變化、圓筒閥在關(guān)閉過(guò)程中閥體的受力情況進(jìn)行分析計(jì)算;最后通過(guò)模擬試驗(yàn),試驗(yàn)結(jié)果表明在模擬試驗(yàn)中,圓筒閥操作機(jī)構(gòu)功能正常,圓筒閥同步性好,動(dòng)作過(guò)程無(wú)卡阻;能夠進(jìn)行真機(jī)的圓筒閥結(jié)構(gòu)及水輪機(jī)的相關(guān)部件的設(shè)計(jì),以及對(duì)圓筒閥機(jī)械液壓控制裝置的成果已經(jīng)能夠用于真機(jī)水輪機(jī)的設(shè)計(jì)。
[Abstract]:In recent years, with the increasing of single turbine capacity and runner diameter, the power station has no longer one-sided pursuit of high efficiency, but put the operation stability in the first place. As a new type of inlet valve, the cylinder valve is installed between the fixed guide vane and the movable guide vane of the turbine. It can act as a water stop valve and can prevent the flow of water from passing through the moving guide vane. When the unit is shut down, the water guide mechanism can be protected well, and the leakage of guide vane caused by clearance cavitation and sediment wear can be avoided. In addition, if the governor is out of order, the cylinder valve can be closed with water if the governor is out of order, thus avoiding the long time runaway state of the turbine generator set, thus protecting the safety of the unit. So it is necessary to study the cylinder valve of Francis turbine. Taking a bidding project as an example, a commercial CFD software CFX14.0 is used to numerically calculate the three-dimensional flow of a hydraulic turbine. The hydraulic characteristics of the cylinder valve under different water head and velocity are obtained by CFD numerical simulation. From this, the optimal geometry of cylinder valve under specific water head and velocity range, the research and development of mechanical hydraulic control device, the relative structure of cylinder valve itself and the top cover and seat ring of hydraulic turbine are studied. Combined with the guide structure of the cylinder valve, the rigid strength and buckling analysis of the cylinder, and the natural vibration frequency of the cylinder, the structural size of the cylinder is determined. It has been possible to use CFD analysis to calculate the variation of velocity field and pressure field in the runner during the closure of the cylinder valve, the pressure characteristics of the inner and outer surface of the cylinder valve body and the changes of the flow field around the valve body. Finally, through the simulation test, the test results show that in the simulation test, the function of the operating mechanism of the cylinder valve is normal, the cylinder valve has good synchronicity, and the movement process is unobstructed. The design of cylinder valve structure and related parts of hydraulic turbine, as well as the results of mechanical hydraulic control device of cylinder valve can be used in the design of real turbine.
【學(xué)位授予單位】：西安理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類(lèi)號(hào)】：TK733.1

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 李穎;李國(guó)曉;劉子祺;孫見(jiàn)波;雷恒;;混流式水輪機(jī)全流道內(nèi)部流場(chǎng)CFD數(shù)值模擬研究[J];電網(wǎng)與清潔能源;2016年04期

2 李文鋒;馮建軍;羅興，

本文編號(hào)：2143821