Study On Hydrodynamic Performance And The Characteristics Of Flow Field Of Horizontal Axis Tidal Current Energy 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 widely used due to its higher power efficient 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 horizontal axis trend to turbine itself and the flow field, and then studied on the hydraulic characteristics of the tidal turbine and the flow field, using Computational Fluid Dynamics (CFD) method, Blade Element Momentum theory (BEM) and experiments.At first, this article introduces the classification of the tidal current energy turbine, analysis the working principle of horizontal axis tidal current energy turbine, puts forward the research content and ideas; Introduces the basic theory to analysis the dynamic performance of tidal current energy turbine, using the combination of basic theory to analysis the hydrodynamic performance of horizontal axis tidal current energy turbine; Through the theoretical calculation shows that pitch Angle of a certain case, the flow velocity greater the blade shaft torque larger; To the flow velocity of a certain case, blade of shaft torque present a first increases with the increase of pitch Angle decreases after change.Using CFD method, build the analysis model of horizontal axis tidal current energy turbine, carry on the simulation analysis of the hydrodynamic performance and the characteristics of the flow field to different forms of horizontal axis tidal current energy turbine under different conditions, preliminary summary the hydrodynamic performance of horizontal axis tidal current energy turbine and the characteristics of flow field;Through the numerical simulation shows: (1) the pitch Angle of a certain situation, the flow velocity greater the blade shaft torque larger; (2) the flow velocity of a certain case, the flow speed blade of shaft torque presents first increases with the increase of Angle of pitch decreases after change; (3) the pitch Angle of a certain case, the flow velocity greater the turbine speed distribution nephogram darker, the turbine speed larger; (4) the flow velocity of a certain case, the speed of the turbine map of color change from shallow to deep with the increase of Angle of pitch, and then change from deep to shallow, the speed of the turbine presents first increases with the increase of Angle of pitch decreases after change; (5) the pitch Angle of certain circumstances, the greater the flow velocity, water turbine flow field around the deeper the color, the velocity distribution of cloud water turbine speed larger;(6) the flow velocity of a certain case, water turbine flow field velocity distribution around the cloud picture color from shallow to deep with the increase of Angle of pitch, and then change from deep to shallow, the speed of the turbine presents first increases with the increase of Angle of pitch after the change. Finally, through model experiment, validate the correctness of the CFD method and BEM method.Based on the research of the hydrodynamic performance of the horizontal axis tidal current energy turbine and the characteristics of the flow field, preliminary reveals the horizontal axis tidal current energy turbine in dynamic properties and the characteristics of flow field under different working conditions, provides a reference and guidance for the horizontal axis tidal current energy turbine to the next step in the turbine tide analysis, provides a theoretical basis for the horizontal axis tidal current energy turbine in engineering application.