Research And Application Of Energy-capturing Area Of Flexible Blade Turbine

Flexible blade turbine is a new type of tidal current energy conversion device. Its blades are made of flexible material. The triangular flexible blades deform under the forces of tidal current. The flexible blade turbine is characteristic with strong self-starting ability, working at low rotational speed. What's more, the flexible blade turbine has the characteristic of engineering development:its rotational direction depends on the installation of flexible blades rather than the direction of fluid. Therefore, the flexible blade turbine can be used in the flow with changeable directions.In this paper we take the energy-capturing areas as the key point of the research, analyze the forces acting on the blades, put forward the concept of energy-capturing area and work out their distribution. Based on the research, we put forward a way of improving the energy capture ability of the turbine through the way of decreasing the negative influence of the negative energy-capturing area. Accomplish the research based on theory analysis, numerical simulation and model experiment.Establish the mathematical model of flexible blade turbine. Do force analysis of the turbine. Claim the existing possibility of the negative energy-capturing area and put forward the test method of numerical simulation and model experiment.Analyze the hydrodynamic characteristics of flexible blade turbine. Simulate the torque of the main-shaft in 12 positions in the whole rotation process; work out the distribution of the energy-capturing areas preliminary. In order to figure out the influence of the energy-capturing area to the energy capture ability, we put forward the concept of submergence degree to research the way to decrease the influence of the negative energy-capturing area. Simulate the torque under different submergence degrees, the result shows that the torque increased at first and then decreased with the decline of the submergence degree. Find the best submergence degree, prove the way of improve the energy capture ability is available. Design and build the experiment model of flexible blade turbine, set up the test and data acquisition system. Test the torque of single-row blades turbine in 12 positions of the whole rotation process, further proof the distribution of energy-capturing areas The torque simulation of the main-shaft under different submergence degree shows that the torque increased at first and then decreased with the decline of the submergence degree, the energy capability of the flexible blade turbine increased about 13% under the best submergence degree. From this point of view, the results proved that the method of improving the energy capture ability is available.Analyze the results of numerical simulation and model experiment. Compare the sum torque of single-row blades turbine with the torque of turbine with full blades under the submergence degree of 100%, analyze the cause of the difference. Put forward the importance of blade compactness research.At last, specific to different environment conditions, design two kinds of engineering projects which are lower-power floating structure and high-power pile structure with lift turbines. Provide the reference to the development of ocean tidal current energy in the future.