减少叶片数后水轮机水力性能的CFD预估及应用
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摘要
针对小型径流式电站卧式水轮机在夏季汛期运行中频繁堵塞而影响正常发电的问题,从增加水轮机出力与过流能力的角度考虑减少叶片数进行改造.利用数值模拟的方法对不同工况下改造前后的水轮机全流道进行数值计算,研究改造前后叶片表面的压力分布,着重分析改造前后叶片数对水轮机水力性能和气蚀性能的影响,得到改造前后的水轮机动力学差异.减少叶片数,叶片间开口增大,机组的防堵塞性能得到改善.计算结果还表明改造后机组可增容6%,最优工况点向大流量区偏移.所得结果可用于HLD06A-WJ-84水轮机的实际改造并指导电站的运行.
Aimed at the serious problem in horizontal turbine in small-scale run-of-river type power station that its operation during summer flood season is frequently by some blockage and its regular power generation is affected thereby, it was considered to remodel it by means of reduction of its number of blades with a view to increasing the flow passage ability and power output of the turbine. Numerical simulation method was used to calculate the full flow passage of the water turbine under different working conditions before and after reduction of number of blades, and the pressure distribution on blade surface was investigated. The influence of number of blades on hydraulic and cavitation performance before and after turbine remodeling was emphatically analyzed, so that the difference of turbine dynamics before and after its remodeling was obtained. When the number of blades was reduced, the opening between two blades would be increased and antiblocking performance of the unit would be improved. The calculation result showed also that the unit capacity would increase by 6% after unit remodeling and the turbine optimal working condition point would shift onto the large flow zone. The result obtained could be used in actual remodelment of HLD06 A-WJ-84 turbine and guide the operation of the power station.
Aimed at the serious problem in horizontal turbine in small-scale run-of-river type power station that its operation during summer flood season is frequently by some blockage and its regular power generation is affected thereby, it was considered to remodel it by means of reduction of its number of blades with a view to increasing the flow passage ability and power output of the turbine. Numerical simulation method was used to calculate the full flow passage of the water turbine under different working conditions before and after reduction of number of blades, and the pressure distribution on blade surface was investigated. The influence of number of blades on hydraulic and cavitation performance before and after turbine remodeling was emphatically analyzed, so that the difference of turbine dynamics before and after its remodeling was obtained. When the number of blades was reduced, the opening between two blades would be increased and antiblocking performance of the unit would be improved. The calculation result showed also that the unit capacity would increase by 6% after unit remodeling and the turbine optimal working condition point would shift onto the large flow zone. The result obtained could be used in actual remodelment of HLD06 A-WJ-84 turbine and guide the operation of the power station.
引文
[1] 刘大恺.水轮机 [M].北京:中国水利水电出版社,2011.
[2] BALAKA R,RACHMAN A,DELLY J.Blade number effect for a horizontal axis river current turbine at a low velocity condition utilizing a parametric study with mathematical model of blade element momentum [J].Journal of Clean Energy Technologies,2014,2(1):1-5.
[3] 施卫东,吴苏青,张德胜,等.叶片数对高比转数轴流泵空化特性的影响 [J].农业机械学报,2013,44(11):72-77.
[4] 付燕霞,袁寿其,袁建平,等.叶片数对离心泵小流量工况空化特性的影响 [J].农业机械学报,2015,46(4):21-27.
[5] 李琪飞,李仁年,韩伟,等.混流式水轮机引水、导水部件内部固液两相流动的数值分析 [J].兰州理工大学学报,2008,34(6):47-50.
[6] 钟苏,王德俊,吕桂萍.混流式水轮机转轮强度的设计优化 [J].大电机技术,2004(4):36-39.
[7] 王福军.计算流体力学分析——CFD软件原理与应用 [M].北京:清华大学出版社,2004.
[8] 敏政,张忠华,罗宏博,等.基于CFD的水轮机导叶翼型数值模拟及分析 [J].兰州理工大学学报,2012,38(3):47-50.
[9] 黄剑锋,张立翔,何士华.混流式水轮机全流道三维定常及非定常流数值模拟 [J].中国电机工程学报,2009,29(2):87-94.
[10] 赖喜德,吉雷,李庆刚,等.基于数值实验的水轮机改造新方法 [J].水利水电技术,2005,6(36):81-84.
[11] 李琪飞,张毅鹏,敏政,等.混流式水泵水轮机密封间隙流动分析 [J].兰州理工大学学报,2016,43(1):51-55.
[2] BALAKA R,RACHMAN A,DELLY J.Blade number effect for a horizontal axis river current turbine at a low velocity condition utilizing a parametric study with mathematical model of blade element momentum [J].Journal of Clean Energy Technologies,2014,2(1):1-5.
[3] 施卫东,吴苏青,张德胜,等.叶片数对高比转数轴流泵空化特性的影响 [J].农业机械学报,2013,44(11):72-77.
[4] 付燕霞,袁寿其,袁建平,等.叶片数对离心泵小流量工况空化特性的影响 [J].农业机械学报,2015,46(4):21-27.
[5] 李琪飞,李仁年,韩伟,等.混流式水轮机引水、导水部件内部固液两相流动的数值分析 [J].兰州理工大学学报,2008,34(6):47-50.
[6] 钟苏,王德俊,吕桂萍.混流式水轮机转轮强度的设计优化 [J].大电机技术,2004(4):36-39.
[7] 王福军.计算流体力学分析——CFD软件原理与应用 [M].北京:清华大学出版社,2004.
[8] 敏政,张忠华,罗宏博,等.基于CFD的水轮机导叶翼型数值模拟及分析 [J].兰州理工大学学报,2012,38(3):47-50.
[9] 黄剑锋,张立翔,何士华.混流式水轮机全流道三维定常及非定常流数值模拟 [J].中国电机工程学报,2009,29(2):87-94.
[10] 赖喜德,吉雷,李庆刚,等.基于数值实验的水轮机改造新方法 [J].水利水电技术,2005,6(36):81-84.
[11] 李琪飞,张毅鹏,敏政,等.混流式水泵水轮机密封间隙流动分析 [J].兰州理工大学学报,2016,43(1):51-55.