摘要
Flow field around a two-bladed horizontal-axis wind turbine(HAWT)is simulated at various tip speed ratios to investigate its wake characteristics by analyzing the tip and root vortex trajectories in the nearwake,as well as the vertical profiles of the axial velocity.Results show that the pitch of the tip vortex varies inversely with the tip speed ratio.Radial expansion of the tip vortices becomes more obvious as the tip speed ratio increases.Tip vortices shed not exactly from the blade tip but from the blade span of 96.5%—99%radius of the rotor.The axial velocity profiles are transformed into V-shape from W-shape at the distance downstream of eight rotor diameters due to the momentum recovery.
Flow field around a two-bladed horizontal-axis wind turbine （HAWT） is simulated at various tip speed ratios to investigate its wake characteristics by analyzing the tip and root vortex trajectories in the near-wake, as well as the vertical profiles of the axial velocity. Results show that the pitch of the tip vortex varies inversely with the tip speed ratio. Radial expansion of the tip vortices becomes more obvious as the tip speed ratio increases. Tip vortices shed not exactly from the blade tip but from the blade span of 96.5%---99% radius of the rotor. The axial velocity profiles are transformed into V-shape from W-shape at the distance downstream of eight rotor diameters due to the momentum recovery.
基金
supported partly by the National Basic Research Program of China(″973″Program)(No.2014CB046201)
the National Natural Science Foundation of China(No.51166009)
the National High Technology Research and Development Program of China(No2012AA052900)
the Natural Science Foundation of Gansu Province
China(No.1308RJZA283
145RJZA059)
the Gansu Province University Scientific Research Project
China(No.2013A-026)
