【摘 要】
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According to the flow separation of NREL Phase VI horizontal axis wind turbine blade,a new flow control method installing vibration micro-cylinder in front of the blade leading edge is proposed.Accord
【机 构】
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School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai,20
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According to the flow separation of NREL Phase VI horizontal axis wind turbine blade,a new flow control method installing vibration micro-cylinder in front of the blade leading edge is proposed.According to the actual flow condition,the fluid solid coupling simulation is conducted where two kinds of micro-cylinder vibration modes are set up,and the aerodynamic performance is numerically studied.The influence of vibration modes and vibration amplitude and frequency on the aerodynamic performance of horizontal axis wind turbine is explored.Numerical results suggest that in the case of different stall conditions,by setting appropriate vibration micro-cylinder can effectively suppress the flow separation on wind turbine blades than installing static micro-cylinder.Besides,the vibration micro-cylinder also shows obvious suppressing effect on large flow separation.When U∞≥13m/s,the vibration direction and vibration amplitude plays a leading role in the improvement of aerodynamic performance,and a micro-cylinder with high vibration frequency can suppress surface flow separation more quickly to achieve the optimum aerodynamic performance.Based on calculation,when U∞=10~25m/s,by setting micro-cylinders which are close to the blade surface with suitable vibration rules,the wind energy coefficient can show increase of 86.2%,188.4%,214.1%,109.8%和120.2%,respectively,compared with those of adding static micro-cylinder or without adding micro-cylinder.
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