摘要
双向流道泵站受长江水位变化影响,易偏离设计工况运行,引发不良压力脉动,影响泵站安全运行。基于雷诺时均方程和SST k-ω湍流模型,对某双向流道泵站模型进行非定常计算,得到设计工况下的压力脉动时间序列,并结合外特性试验对计算结果予以验证。为研究双向流道泵站压力脉动的混沌特性,对压力脉动的时间序列进行相空间重构,求取最大李雅普诺夫指数、关联维数、分形标度3个混沌特性参数并进行分析。研究表明:各监测点压力脉动的最大李雅普诺夫指数均大于0,表明计算得到的压力脉动时间序列具有混沌特性;叶轮出口处P_(9)点的关联维数最大,出水喇叭口处P_(18)点关联维数最小,与压力脉动振幅变化大小相对应;分形标度均大于0,导叶中部P_(15)点分形标度值最大,代表在此情况下混沌特性最强。
Affected by the change of water level in the Changjiang River,the bidirectional channel pumping station is easy to deviate from the design condition,causing bad pressure fluctuation and affecting the safe operation of pumping stations.The unsteady calculation based on RANs equation and SST k-ωturbulence model is used on abidirectional channel pumping station model for obtaining the pressure fluctuation time series under the design conditions.The results are verified by external characteristic tests.In order to study the chaotic characteristics of pressure fluctuation in bidirectional channel pumping station,the phase space reconstruction of time series is carried out,and the maximum Lyapunov exponent,correlation dimension and fractal scale are calculated and analyzed.The study shows that the maximum Lyapunov exponent of each monitoring point is more than 0,indicating that the time series have chaotic characteristics.P_(9)at the impeller outlet has the largest correlation dimension,and point 18 at the outlet horn outlet has the smallest,which is corresponding to the of pressure fluctuation amplitude.The fractal scales are all more than 0,and the fractal scale value at P_(15)in the middle of the guide vane is the largest,indicating that the chaotic characteristics are the strongest in this case.
作者
肖忠明
颜红勤
蒋红樱
成立
刘志泉
XIAO Zhong-ming;YAN Hong-qin;JIANG Hong-ying;CHENG Li;LIU Zhi-quan(Jiuqu River Administration Office of Danyang City,Zhenjiang 212000,Jiangsu Province,China;Hydraulic Engineering Science and Technology Consultation Limited Company of Jiangsu Province,Nanjing 210029,China;College of Hydraulic Science and Engineering,Yangzhou University,Yangzhou 225009,Jiangsu Province,China)
出处
《中国农村水利水电》
北大核心
2022年第9期13-18,共6页
China Rural Water and Hydropower
基金
国家自然科学基金(51779214)
江苏水利科技项目(2019014)(2020027)。
关键词
双向流道泵站
混沌理论
压力脉动
相空间
李雅普诺夫指数
bidirectional channel pumping station
chaos theory
pressure fluctuation
phase space
Lyapunov exponent
