No abstract

Wind energy has seen a rapid growth worldwide. Wind turbines are typical devices that convert the kinetic energy of wind into electricity. Researches in the past have proved that Vertical Axis Wind Turbines (VAWTs) are more suitable for urban areas than Horizontal Axis Wind Turbines (HAWTs). In the present design of the VAWT, the power prodused depends on the drag force generated by the individual blades and interactions between them in a rotating configuration. Numerical simulation for the aerodynamics of VAWT with tow different rotors (Three and Foure blades ) having movable vanes are curred out. The For numerical simulation, commercially available computational fluid dynamic (CFD) softwares GAMBIT and FLUENT are used. In this work the Shear Stress Transport (SST) k-ω turbulence model was used which is better than the other turbulence models available as suggested by some researchers. The predicted results show agreement with those reported in the literature for VAWT having different blades designs.

In this study, the aerodynamic performance of a car spoiler with tubercles configurations that was inspired by Humpback whale flipper morphology was investigated. This was done by producing three (T0, T3, and T9) spoiler designs where, tubercles sinusoidal protrusions pattern was applied at the leading edge of the spoiler. T0, is a base line spoiler that has no tubercles, T3, that contains three tubercles protrusions, and T9, contains nine tubercle protrusions. The baseline spoiler design was based on the Selig s2091 spoiler and the spoiler has a chord length (C) 100mm and 290mm wingspan. The spoiler was tested angle of attack from - 20 to 30° and at Reynolds number 60000 in an open circuit subsonic wind tunnel. The aerodynamic performance of the spoiler was measured by the recorded time averaged lift and drag. From the recorded it was observed that at certain angles of attack, the presence of a tubercle pattern can bring a significant aerodynamic improvement.