Study On Hydrodynamic Characteristics And Efficiency Of The Nodding Duck Wave Power Device

With the rapidly development of society and economy, the large-scale use and consumption of fossil fuels make the problem in energy and environment become more and more serious. Every country around the world is actively engaged in the development and utilization of clean and renewable energy. Ocean energy, as one of clean and renewable energy sources, has increasingly become the focus of attention. "Nodding duck" wave energy device is an efficient wave energy conversion device. The study on it has an important meaning for the development of ocean energy and further for the development of clean and renewable energy.This paper studied the hydrodynamic characteristics and energy harvesting efficiency of the device. In response to this topic, firstly, theoretical analysis on the first order stokes wave was conducted by given the first order stokes wave equations and boundary conditions. On the basis of it, a two dimensional numerical wave tank was established in FLUENT software, generating waves by moving the wall boundary at the beginning of the tank and realizing waves by adding damping source term at the end of it. Moreover, its effectiveness of generating and realizing waves was verified. Secondly, according to the governing equations and the boundary conditions of the device moving on the free water surface, the theoretical analysis of added mass and added damping was given. And based on the numerical calculation principle of added mass and added damping, the added mass and added damping of device was solved and calculated by the numerical simulation ways. Finally, with all the above work, analysis about the spatial stress of device had been carried out. And a fluid-structure model of the coupling interaction of energy harvesting device and wave had been established. Then the numerical simulation had been carried out. According to the simulation results, the force and movement of the Duck wave energy device under the action of waves were analyzed, and then from the perspective of wave energy, the wave energy conversion efficiency of the device was analyzed, which could be a reference for the practical application promotion and further study of the “Nodding Duck” wave energy device.