High wind velocities are required for wind projects to be economically efficient. To increase the wind speed, the concept of ducted wind turbines has been introduced in recent decades. Among them is the Invelox, which can capture the wind from all directions and funnel the collected air to the ground level. Primary results have shown that this design can increase the overall efficiency of a wind project. In this study, the effects of the main geometrical parameters affecting the aerodynamic performance of the Invelox are numerically studied. The effects of the inlet area, the diameter of the Venturi section and the height of the funnel on the wind speed increment inside the Venturi section have been determined. Results show that the inlet area and the Venturi cross section area have the most significant effects on the speed ratio (SR) of the Invelox, while the funnel height and air velocity have minor effects. In the case of appropriate selection of the geometry parameters, velocity increments up to 1.9 are achievable. Finally, the effects of adding a horizontal axis wind turbine inside the Venturi on its power coefficient are studied. Results show that Invelox greatly enhances the turbine maximum power coefficient. However, it decreases the tip speed ratio corresponding to the maximum power coefficient.

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Numerical study on the geometrical parameters affecting the aerodynamic performance of Invelox

References

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