本文選題：混流式水輪機 + 導葉分布圓直徑　； 參考：《西安理工大學》2017年碩士論文

【摘要】：中小型電站的技術改造在現(xiàn)在的水電發(fā)展事業(yè)中擔任著極其重要的角色,借助CFD軟件來研究過流部件參數(shù)變化對水輪機性能的影響對于水電站的改造具有一定的借鑒意義。本文以HLX180-LJ-36水輪機為研究對象,通過CAD、UG等軟件對機組進行改型,借助CFD軟件對改型前后的水輪機進行流動分析。首先,根據(jù)所給的CAD圖紙對水輪機進行三維全流道建模,然后對建立好的模型進行網格劃分,最后通過CFX軟件進行計算及后處理。通過修改導葉分布圓直徑,下環(huán)以及轉輪出口直徑研究過流部件參數(shù)變化水輪機性能的影響。得出以下結論:(1)導葉分布圓直徑的變化對最優(yōu)工況和大流量工況下水輪機的內部流動影響不大,但是對小流量工況下的葉道渦影響較大;水輪機的效率隨著導葉分布圓直徑的增大而增加,小流量工況表現(xiàn)尤為突出,與原轉輪相比,小流量工況時,方案5的效率提高了1.87%,在大流量工況時,效率提高了 0. 17%,最優(yōu)工況時提高了 0. 04%;隨著導葉分布圓直徑的增大,活動導葉和轉輪之間無葉區(qū)的壓力脈動有所減輕。(2)下環(huán)形狀和轉輪出口直徑對不同工況下水輪機性能的影響不同。增大轉輪出口直徑和下環(huán)錐角可以提高水輪機的過流能力,但是在小開度工況下,由于效率下降太多導致水輪機的出力整體下降;最優(yōu)開度下,水輪機的效率會有所下降,但是由于過流量的增加,水輪機的出力整體增加,相比于原方案,方案4增容5.4%:大開度工況下,水輪機的效率和過流量都增加,相比原方案,方案4增容8. 3%。(3)增大轉輪出口直徑和下環(huán)錐角,水輪機的最優(yōu)工況將向大流量方向偏移,水輪機的空化性能略微有點下降。(4)適當?shù)脑龃筠D輪出口直徑和下環(huán)錐角可以減小小開度工況下水輪機轉輪的出口環(huán)量,減輕尾水管的壓力脈動。
[Abstract]:The technical transformation of small and medium-sized power stations plays an extremely important role in the development of hydropower stations at present. The study of the influence of the parameters of the flow passing components on the performance of the turbine by means of CFD software has certain reference significance for the transformation of hydropower stations. In this paper, HLX180-LJ-36 turbine is taken as the research object, the turbine is modified by CAD / UG software, and the flow analysis of the turbine before and after the modification is carried out with the help of CFD software. Firstly, according to the CAD drawings, the three-dimensional full-channel modeling of the turbine is carried out, then the established model is meshed, and the calculation and post-processing are carried out through the CFX software. By modifying the diameter of the guide vane distribution circle, the lower ring and the outlet diameter of the runner, the influence of the parameters of the overflowing parts on the performance of the turbine is studied. The following conclusions are drawn: (1) the variation of the diameter of the distribution circle of the guide vane has little effect on the internal flow of the turbine under the optimal condition and the large flow condition, but has a great effect on the vortex of the blade under the condition of small flow rate; The efficiency of the turbine increases with the increase of the diameter of the distribution circle of the guide vane, and the performance of the small flow rate is particularly prominent. Compared with the original runner, the efficiency of the scheme 5 is increased by 1.87 in the case of small flow, and by 0. 7 in the case of the large flow rate. In the optimal operating conditions, the increase of 0. 5%. With the increase of the diameter of the guide vane distribution circle, the pressure pulsation in the vaneless zone between the active guide vane and the runner can be alleviated.) the influence of the lower ring shape and the runner outlet diameter on the performance of the turbine is different under different working conditions. Increasing the diameter of runner outlet and the cone angle of the lower ring can improve the overflow capacity of the turbine, but under the condition of small opening degree, the efficiency of the turbine will decrease as a whole because of too much decrease in efficiency; under the optimal opening, the efficiency of the turbine will decrease. However, due to the increase of overflow rate, the output capacity of the turbine increases as a whole. Compared with the original scheme, scheme 4 increases the capacity of the turbine by 5.4: under the condition of large opening, the efficiency and overflow rate of the turbine increase, compared with the original scheme, the capacity of the fourth scheme increases by 8. Increase the diameter of runner outlet and the conical angle of lower ring, the optimal working condition of the turbine will shift to the direction of large flow rate, The cavitation performance of the turbine is slightly decreased. 4) increasing the outlet diameter of the runner and the cone angle of the lower ring can reduce the outlet ring quantity of the turbine runner under the condition of small opening and reduce the pressure pulsation of the draft tube.
【學位授予單位】：西安理工大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TV734

【參考文獻】

相關期刊論文 前10條

1 何楊;劉又文;;水輪機水動力效率性能優(yōu)化方法研究[J];計算機仿真;2017年02期

2 馮漢擴;朱鵬艷;;超低比轉速軸流式水輪機蝸殼優(yōu)化[J];吉林水利;2017年01期

3 王旭;張佳芬;盧婧;盧磊;;水輪機轉輪葉片割邊改造的CFD與模型試驗分析[J];機械設計與制造;2017年01期

4 楊中瑞;李愛民;余建軍;;小型立軸混流式水輪機增效擴容改造選型及流道匹配[J];小水電;2016年05期

5 林華;岳婷;張蒙;;混流式水輪機轉輪優(yōu)化設計及CFD分析[J];機械;2016年09期

6 趙永智;劉德民;荀洪運;;基于CFD分析的水泵水輪機活動導葉優(yōu)化設計[J];東方電氣評論;2016年03期

7 羅麗;賴喜德;朱李;李景悅;;混流式水輪機改造前后內部流動特性對比分析[J];水力發(fā)電學報;2016年08期

8 文相;;探究中小型水電站水輪機增效擴容改造方案[J];通訊世界;2016年16期

9 邢正鋒;;小型水電站增容改造中存在的問題及對策措施[J];農業(yè)科技與信息;2016年22期

10 羅麗;李景悅;;混流式水輪機內部空化流動數(shù)值模擬[J];人民長江;2016年13期

相關會議論文 前1條

1 趙妍;羅興，

本文編號：1847725