Experimental study of the effect of a slat angle on double-element airfoil and application in vertical axis wind turbine

Abstract

A design of double-element airfoil is proposed for its use in the vertical axis wind turbine. The double-element airfoil system consists of a main airfoil and a slat airfoil. The design parameters of the double-element airfoil system are given by the position and orientation of the trailing edge of the slat airfoil with respect to the nose of the main airfoil. The position parameters are given by x_TE and y_TE. The orientation is given by the slat angle β_s; it is the angle between the chord lengths of the slat airfoil with respect to the main airfoil. Various tests were performed using different slat angles at various Reynolds numbers to measure the aerodynamic characteristics, so as to study the slat angle effects. The variation in the slat angle causes a change in the lift coefficient of the double-element airfoil considerably. Therefore, an optimum value of slat angle is determined for the double-element airfoil system designed in this paper. Further, the performance of new design of a vertical axis wind turbine shows considerable increase in the power coefficient and the total power output as compared to the reference wind turbine.

Keywords:

• double-element airfoil
• wind tunnel testing
• vertical axis wind turbine design
• offshore application

Additional information

Funding

The SYSWIND project (project no. 238325) funded by the Marie Curie Actions is acknowledged for the financial support under the grant Seventh Framework Programme for Research and Technological Development of the EU [grant number PITN-GA- 2009-238325].