底铰摆式波浪能装置群水动力性能研究

HYDRODYNAMICS BY ARRAYS OF BOTTOM-HINGED FLAP-TYPE WAVE ENERGY CONVERTERS

对常水深等厚度底铰摆式波浪能装置群,为减少多个装置物面上的网格数量,采用变量分离法将三维空间速度势表示成二维平面速度势和垂向特征函数相乘的形式,并利用二维格林函数法求解平面绕射势和辐射势,解决波浪与波浪能装置群之间的相互作用问题。利用所建立的数值模型分析波浪发电场装置之间的间距对各装置波能俘获效率、波浪发电场平均俘获效率及总输出功率随时间变化的波动率的影响。与单个孤立底铰摆式波能转换装置比较,以阵列形式布置的装置群,其总输出功率随时间变化的波动率在大部分波浪周期范围可明显降低,其降低程度主要与沿波浪传播方向的装置间距有关。

In order to reduce the surface mesh numbers for bottom-hinged flap-type wave energy converter arrays with the same section in water of constant depth,separation of variables is adopted. Accordingly,the three-dimensional spatial velocity potential can be expressed as a product of functions of two-dimensional spatial velocity potential and the vertical eigenmodes. And the two-dimensional Green’s function method can be used to calculate the 2D spatial diffraction and radiation potentials and then the interactions between waves and wave energy converter arrays. By using the numerical model based on the developed theory,the impact on the capture efficiency of each wave energy converter in arrays,the mean capture factor of a wave farm and the total output power fluctuation with time are analyzed. Compared with a single isolated bottom-hinged flap-type wave energy converter,the fluctuation rate of the total output power for the whole array with time can be significantly reduced in most wave periods,and the reduction degree is mainly related to the spacing of converters along the wave propagation direction.