DESIGN AND WIND TUNNEL TESTING OF A SAVONIUS WIND TURBINE INTEGRATED WITH THE OMNI-DIRECTION-GUIDE-VANE

摘要

A novel omni-direction-guide-vane (ODGV) that surrounds a vertical axis wind turbine (VAWT) is designed to improve the wind turbine performance. A scaled model was constructed to simulate a Savonius VAWT enclosed by the ODGV on top of high-rise building for wind tunnel testing. Torque, rotational speed and power output were measured using a torque transducer with hysteresis brake applied to the rotor shaft. With the aid of the ODGV, the highest increment in rotational speed (11.4%) was achieved at a wind speed of 3 m/s (at free-running condition). The ODGV also increased the power coefficient, C_p of the VAWT at all tested wind speeds and the maximum (C_p = 0.26) was achieved at the tip speed ratio, TSR = 0.95 for a wind speed of 3 m/s. The highest increment of C_p (56.9%) was obtained at the same TSR and wind speed. With this design, the size of VAWT can be reduced for a given power output.