摘要
在含沙水流中运行的水斗式水轮机,分水刃和缺口是斗叶上最容易受到磨损变形的部位。采用欧拉-拉格朗日法对水-气-砂三相流进行非定常计算,研究分水刃高度下降对流态及泥沙磨损的影响,以及分水刃高度、缺口深度变化对转轮外特性的影响。研究发现:分水刃高度下降会对流线产生影响,在进水侧区域诱发旋涡和湍流,致使流态紊乱,水力损失增加,从而造成转轮外特性下降。当分水刃高度下降2、5、10mm时,转轮的效率分别减少了0.22%、0.66%、5.98%。分水刃高度下降造成的斗叶型线变化,会影响泥沙颗粒对斗叶内壁面的磨损情况。分水刃下降的高度越大,分水刃区域的磨损越严重、磨损范围越大。缺口深度增加会减小斗叶工作面面积,造成转轮外特性下降。尤其是当缺口深度增加10mm时,效率降低了15.37%,转轮效率低于70%,在这种工况下运行,对射流能量的利用是非常不利的。
For Pelton turbines operating in sediment-laden flow,the splitter and cutout are the most vulnerable parts of buckets.In this paper,the unsteady calculation of water-air-sand three-phase flow was carried out by using the Eulerian-Lagrangian method.The flow pattern after eroded,the influence of the splitter height on sediment erosion,and the effects of the splitter height and cutout depth on the runner performance were studied.It was found that the decrease of the splitter height would affect the streamline,and induce the vortex and turbulence in the bucket inlet zone,resulting in the disorder of the flow pattern.Therefore,the hydraulic loss would increase,and the external characteristics of the runner would decrease.When the slitter's height decreased by 2 mm,5 mm,and 10 mm,the runner's efficiency decreased by 0.22%,0.66%,and 5.98%,respectively.The variation of the bucket profile caused by the decrease in the height of the splitter would affect the sediment erosion on the inner surface of the bucket.The greater the decrease of the splitter height was,the more severe erosion of the splitter zone was.The increase of cutout depth would reduce the bucket working area,resulting in a decrease of the runner's external characteristics.When the cutout depth increased by 10 mm,the efficiency decreased by 15.37%,and the runner efficiency was lower than 70%.Under this condition,the utilization of jet energy was insufficient.
作者
葛新峰
孙洁
蔡建国
张雷
张辉
王金亮
MAXIME Binama
郑源
GE Xinfeng;SUN Jie;CAI Jianguo;ZHANG Lei;ZHANG Hui;WANG Jinliang;MAXIME Binama;ZHENG Yuan(College of Energy and Electric Engineering,Hohai University,Nanjing 210098,Jiangsu Province,China;Chongqing Shipping Construction and Development Co.,Ltd.,New North District,Chongqing 401121,China;Yellow River Institute of Hydraulic Research,Zhengzhou 450003,Henan Province,China;Huanghe Wanjiazhai hydro Junction Co.,Ltd.,Pianguan 036412,Shanxi Province,China)
出处
《中国电机工程学报》
EI
CSCD
北大核心
2021年第21期7391-7402,共12页
Proceedings of the CSEE
基金
中央高校基本科研业务费(2015B02814)
国家自然科学基金项目(51579080)。
关键词
水斗式水轮机
泥沙磨蚀
分水刃
缺口
水-气-砂三相流数值模拟
Pelton turbine
sediment erosion
splitter
cutout
numerical simulation of water-gas-sand three-phase flow
