Study On Blade Optimization And Hydrodynamic Performance Of Horizontal Axis Marine Current Turbine

Tidal current energy is one kind of rich marine energy and it is predictable and stable.Nowadays, horizontal axis tidal current energy turbine is wildly used due to its higher powerefficient and many institutes have already done some research and experiments on it. However,because of lack of abundant research, the development of tidal current energy is still in its infancy.This article focused on the optimal design of turbine blades firstly and then studied on the hydrauliccharacteristics of the tidal turbine using Computational Fluid Dynamics (CFD) method, BladeElement Momentum theory (BEM) and experiments.At first, an investigation was performed on the state of the art of tidal power technology in theworld, analyzed current parameters of existing tidal turbines and proposed study content andmethodology afterwards; introduced the basic theories of blades design and its performance analysis,figured out performance parameters of turbine blades by using an airfoil design and analysisprogram-Profili; following the optimization principle, the blade parameters were calculated andgeometry model was created by3D design program-Solidworks.The physics model of tidal turbine blades was created and simulations were operated usingCFD program Fluent. The hydrodynamic performance was gained by analyzing the simulationresults from varies of cases under different operating conditions; combining with BEM theory, themathematical model generating power coefficients and thrust coefficient was established and thecharacteristic parameters could be gained rapidly using programming calculation; based on previousresults, in order to improve power coefficient of horizontal axis turbine, the characteristics ofdifferent form guide diffusers were studied, the influence dimension parameters were analyzed andthe structure were optimized; By comparing and analyzing the CFD simulation results onhydrodynamic performance of the two cases: with guide diffuser and without guide diffuser, it wasproven that the application of guide diffuser could improve the power coefficient of turbinesignificantly; in the end, the results of CFD were verified by model tests.In this article, by analyzing the hydrodynamic characteristics of turbine under differentoperating conditions, the hydrodynamic performances of tidal current energy horizontal axis turbinewere revealed initially. Hopefully, the study results could provide reference and guidance for thefuture research on hydrodynamic characteristics of axial tidal power turbine and its application inengineering.