The performance and wake structure of a model vertical axis wind turbine (VAWT)is studied, subject to various blade geometries, modes of operation, and inflow conditions. To facilitate this investigation, the neutral atmospheric boundary layer (ABL) must be simulated in a short recirculating wind tunnel. This is achieved using a modified form of Counihan’s method, composed of passive devices including a barrier wall, elliptical vortex generators, and wall roughness elements. Improvements to these elements resulted in a 1∶1000 scale representation of the neutral ABL, with turbulence characteristics that match well with both rough wall boundary layer measurements and full-scale atmospheric measurements alike. Good span wise and stream wise uniformity of this simulated ABL was achieved in only five boundary layer depths,δ,allowing approximately half of the wind tunnel test section for turbine measurements…
Author: Tristen Charles Hohman
Publication: Princeton University
Year Published: 2017