Wind turbine blade with a gurney flap

Wind turbine blade having a length (L), an airfoil with a local chord (C), and a first Gurney flap attached to a pressure or a suction surface of the airfoil near a trailing edge of the wind turbine blade,

• said first Gurney flap extending along at least 50% of a length of an outer ⅓rd of the wind turbine blade;
• and
• the first Gurney flap comprises a first surface which is attached to the pressure or the suction side of the wind turbine blade and a second surface facing a direction of travel of the wind turbine blade, and in that, in a perpendicular cross section through the first Gurney flap, said first Gurney flap is arranged such that an average normal vector of the second surface forms an angle (A) ranging from positive 30 degrees to negative 30 degrees to the local chord (C) of the airfoil and in that a height (H) of the first Gurney flap is greater than 0.1% and less than 0.5% of a length of the local chord of the airfoil;
• wherein the perpendicular cross section is through the first Gurney flap and airfoil, a dimension (D1), along a direction which is parallel to the local chord (C) of the airfoil, from the trailing edge of the wind turbine blade to a point of the second surface which is located furthest from the first surface of the first Gurney flap in a direction perpendicular to the local chord of the airfoil is less than 0.5% of the length of the local chord of the airfoil.