WIND-TUNNEL PERFORMANCE DATA FOR 2-BUCKET AND 3-BUCKET SAVONIUS ROTORS

Fifteen configurations of a Savonius rotor wind turbine were tested in the Vought Corporation Systems Division 4. 9- multiplied by 6. 1-m Low Speed Wind Tunnel to determine aerodynamic performance. The range of values of the varied parameters was as follows: number of buckets, 2 and 3; nominal freestream velocity, 7 and 14 m/s; Reynolds number per meter, 4. 32 multiplied by 10**5 and 8. 67 multiplied by 10**5; rotor height, 1 and 1. 5 m; rotor diameter (nominal), 1 m; bucket overlap, 0. 0-0. 1 m. The measured test variables were torque, rotational speed, and tunnel conditions. It is concluded that increasing Reynolds number and/or aspect ratio improves performance. The recommended configuration consists of two sets of two-bucket rotors, rotated 90 deg apart, with each rotor having a dimensionless gap width of 0. 1-0. 15.