Research On Hydrodynamic Performance Of Bouy-Chain-Sprocket Wave Energy Device

Oscillating buoy wave energy convertor is a hot spot of wave energy research and development at home and abroad these years due to its simple structure,low manufacturing and maintenance cost,high efficiency and so on.The Buoy-Chain-Sprocket wave energy device belongs to the oscillating wave energy device,which has the advantages of strong survivability and low cost of wave energy collection in extreme environment,and has the characteristics of one-way wave energy collection.The existing literatures on the hydrodynamic performance of oscillating buoy wave energy convertor are all aimed at the wave energy devices with two-way acquisition characteristics,so it is difficult to meet the characteristic requirements of Buoy-Chain-Sprocket wave energy device.In view of the above characteristics,the hydrodynamic performance of Buoy-Chain-Sprocket wave energy device with one-way wave energy acquisition characteristics is studied systematically in this paper.The main contents are as follows:Based on the linear potential flow theory and the first-order radiation theory,the radiation problem of the truncated cylinder is solved by using the eigenfunction expansion and the asymptotic function matching method,the dispersion relations of various wave conditions are calculated,and the expression of the hydrodynamic coefficient of the device is obtained.One computing program is developed to calculate the hydrodynamic coefficients,and their frequency domain variation curves of the model test device and sea test device under various wave conditions are obtained.According to the characteristics of one-way acquisition of this device,the hydrodynamic modeling is carried out based on the idea of piecewise function,and a program is compiled to realize the variable parameter solution of the hydrodynamic differential equation of the device,which makes up for the deficiency of the commercial software.The hydrodynamic response of the device is calculated.By using a simpler and more accurate integration method,the first-level average collection power of the device is obtained.Based on the physical model test,the effects of parameters such as wave condition,floating body mass,counterweight mass and damping force on the hydrodynamic performance of the physical model are studied,and the analytical calculation method of hydrodynamic performance proposed in this paper is verified and improved.Based on the hydrodynamic analytical calculation method of wave energy collection in this paper,taking the average acquisition power of first-level wave energy as the optimization objective,the hydrodynamic performance of Buoy-Chain-Sprocket wave energy device under three typical wave conditions is optimized.The results show that the connection of the Buoy-Chain-Sprocket response curve is smooth and continuous in the rising stage and falling stage,and the three wave conditions all have the characteristics of one-way wave energy acquisition,and compared with the results before optimization,the average acquisition power of first-level wave energy of the three wave conditions has been significantly improved.