Vortex generator for a wind turbine rotor blade

1 . A vortex generator for a wind turbine rotor blade, the vortex generator comprising:

a base plate arranged in a base plate plane and having a lower surface configured for being mounted to an outer surface of the wind turbine rotor blade, an upper surface opposite the lower surface, a front edge, and a rear edge;

said base plate defining a longitudinal axis;

said rear edge of the base plate including a perpendicular section arranged perpendicular to the longitudinal axis;

at least one plate-shaped fin having a first longitudinal section arranged at said upper surface of the base plate and a second longitudinal section extending beyond said rear edge and having a lower edge which is not connected to said base plate;

said first longitudinal section including a rear part arranged rearwards of said perpendicular section; and,

said base plate including a first stiffening section arranged rearwards of said perpendicular section and forming a transition to said rear part.

2 . The vortex generator of claim 1 , wherein said first stiffening section has a length measured in a direction of said longitudinal axis and a width measured in a direction perpendicular to said longitudinal axis; and, said length is in a range of 20% to 100% of said width.

3 . The vortex generator of claim 1 , wherein said first stiffening section has a length measured in a direction of said longitudinal axis; and, said perpendicular section is a straight line as long as or longer than said length of said first stiffening section.

4 . The vortex generator of claim 1 , wherein said perpendicular section is a point on a curved line describing said rear edge of said base plate.

5 . The vortex generator of claim 1 , wherein said front edge is a straight line arranged perpendicular to said longitudinal axis.

6 . The vortex generator of claim 1 , wherein said first stiffening section has a triangular shape with a straight edge leading from the perpendicular section to a rear end of the rear part.

7 . The vortex generator of claim 1 , wherein said first stiffening section has a concavely curved edge leading from said perpendicular section to a rear end of said rear part.

8 . The vortex generator of claim 1 , wherein said first stiffening section has a thickness which is equivalent to a thickness of an adjacent section of said base plate.

9 . The vortex generator of claim 1 , wherein the vortex generator has exactly one plate-shaped fin; and, said first stiffening section is arranged on a first side of said plate-shaped fin.

10 . The vortex generator of claim 9 , wherein said base plate includes a second stiffening section arranged on a second side of said plate-shaped fin opposite said first side.

11 . The vortex generator of claim 10 , wherein said base plate has a trapezoidal, rectangular, hexagonal or circular shape supplemented by at least one of said first stiffening section and said second stiffening section.

12 . The vortex generator of claim 1 , wherein the vortex generator has exactly two plate-shaped fins including a first plate-shaped fin and a second plate-shaped fin arranged symmetrically with reference to said longitudinal axis; each of said two plate-shaped fins has an inner side facing towards said longitudinal axis; said first stiffening section is arranged at said inner side of said first plate-shaped fin; and, said base plate includes a second stiffening section arranged at the inner side of said second plate-shaped fin.

13 . The vortex generator of claim 1 , wherein the vortex generator is produced in one piece using an injection molding process or wherein the vortex generator is produced from one piece of sheet metal.

14 . A vortex generator for a wind turbine rotor blade, the vortex generator comprising:

a base plate arranged in a base plate plane and having a lower surface configured for being mounted to an outer surface of the wind turbine rotor blade, an upper surface opposite the lower surface, a front edge, and a rear edge;

said base plate defining a longitudinal axis;

said rear edge of the base plate including a perpendicular section arranged perpendicular to the longitudinal axis;

at least one plate-shaped fin having a first longitudinal section arranged at said upper surface of the base plate and a second longitudinal section extending beyond said rear edge and having a lower edge which is not connected to said base plate;

said first longitudinal section including a rear part arranged rearwards of said perpendicular section;

said base plate including a first stiffening section arranged rearwards of said perpendicular section and forming a transition to said rear part;

said first stiffening section having a concavely curved edge leading from said perpendicular section to a rear end of said rear part;

said concavely curved edge having a radius of curvature and said at least one plate-shaped fin has a maximum height; and,

said radius of curvature being in a range of 30% to 100% of said maximum height.

15 . A wind turbine rotor blade comprising:

a wind turbine rotor blade body having a rotor blade outer surface;

at least one vortex generator including a base plate arranged in a base plate plane;

said base plate having a lower surface configured for being mounted to an outer surface of the wind turbine rotor blade, an upper surface opposite the lower surface, a front edge, and a rear edge;

said base plate defining a longitudinal axis;

said rear edge of the base plate including a perpendicular section arranged perpendicular to the longitudinal axis;

said at least one vortex generator further including at least one plate-shaped fin having a first longitudinal section arranged at said upper surface of the base plate and a second longitudinal section extending beyond said rear edge and having a lower edge which is not connected to said base plate;

said first longitudinal section including a rear part arranged rearwards of said perpendicular section;

said base plate including a first stiffening section arranged rearwards of said perpendicular section and forming a transition to said rear part; and,

said at least one vortex generator being mounted on said rotor blade outer surface.