摘要
将浮式垂直轴叶轮在波浪中运动的水动力学问题简化为其在均匀流中受到强迫摇荡运动.通过二次开发ANSYS-CFX软件建立了这种强迫摇荡的水动力学模型,计算了垂直轴叶轮绕自身主轴旋转的同时发生单自由度受迫横摇运动时的水动力性能,分析了不同受迫横摇运动频率对叶轮推力和侧向力的影响,通过对计算的推力和侧向力进行傅里叶级数展开并进行最小二乘法拟合,得到了与水轮机受迫横摇运动速度和加速度相关的阻尼和附加质量傅里叶级数系数.计算结果表明：受迫横摇运动下的叶轮效率、推力和侧向力曲线的上下包络线明显按照横摇频率发生周期性波动;随着横摇频率的增加,推力和侧向力系数包络线波动幅值会随之增大,但平均值几乎不变;不同横摇频率下,在推力中阻尼项有较大的占比,而在侧向力中阻尼力和附加质量力几乎相当.浮式立轴叶轮在波流作用下的摇荡运动对潮流能装置的结构强度和疲劳特性有很大影响.研究结果对波流作用下的浮式潮流能装置水动力特性的研究有较大的工程和学术意义.
The hydrodynamic problems of the floating vertical-axis tidal turbine in waves are simplified as the forced sloshing motions in the uniform flow in this paper.The hydrodynamic performance of the tidal turbine with self-axis rotation and forced rolling motion by the establishment of the coupled hydrodynamic model with the redevelopment of ANSYS-CFX.The thrust and lateral forces of the turbine with different forced motion frequencies are calculated and analyzed.The Fourier series coefficients of the damping and assed mass coefficients linked with the velocity and acceleration of forced motion are obtained through the Fourier expansion and least square fitting on the calculated thrust and lateral forces before.The numerical results show that the time-varying efficiency and load curves of the rotating turbines exhibit an additional fluctuation.The fluctuation amplitudes of thrust and lateral force＇s envelope curves have a positive correlation with the frequency of the rolling motion with their mean values are slightly affected.The damping term has a larger proportion in the rolling thrust for different rolling frequencies,and the damping and the additional mass forces are almost equal in the lateral force.The sloshing motions of the turbine in the combined complex environment has a great effect on the structure strength and fatigue characteristics.The study of this paper has great engineering and academic significance for the study of the hydrodynamic characteristics of a floating tidal current power station under the action of waves and flow.
作者
张万超
王凯
王树齐
国威
Zhang Wanchao;Wang Kai;Wang Shuqi;Guo Wei(School of Naval Structure and Ocean Engineering,Jiangsu University of Science and Technology,Zhenjiang 212003,Jiangsu China;Wuhan Second Ship Design ＆ Research Institute,Wuhan 430064,China;State Key Laboratory of Hydrodynamics,China Ship Scientific Research Center,Wuxi 214082,Jiangsu China)
出处
《华中科技大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2018年第8期18-23,共6页
Journal of Huazhong University of Science and Technology(Natural Science Edition)
基金
国家自然科学基金资助项目(51709137,51579055)
关键词
立轴水轮机
横摇运动
阻尼系数
附加质量系数
水动力性能
vertical-axis tidal turbine
rolling motion
damping coefficients
added mass coefficients
hydrodynamic characteristics
作者简介
张万超（1989-），男，讲师，E-mail：wanchao_zhang@foxmail．com．
