Vojislav Kujundzic from Ivanjica has applied his invention called “Wing Wind Turbine with a Vertical Rotating Axis” at the Institute for Intellectual Property of the Republic of Serbia. According to the description, the invention is based on a large difference in aerodynamic resistance of two-part blades, rotors and wind turbines when rotating around the vertical axis.
The invention entails a changeable shape of the blades, whose parts expand or fold down relative to their radial carrier depending on the position during the rotation around the vertical axis and the direction of the wind.
In the active sector of the wind's impact, the blades, previously folded into a horizontal package, open and expand, increasing the resistance of the blade with a vertical aerodynamic surface of the radial carrier. The open blade, with its large surface, along with the carrier, passes through the active zone of the wind's impact. While in the non-active zone, the wind, now on the rear side of the two-part blade, folds down its wings into a horizontal package and hides them behind the radial carrier. Thus folded, the blades, while rotating, do not provide resistance to the wind current.