Patents by Inventor Dan Christian Bak

Dan Christian Bak has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8419363
    Abstract: A deformable trailing edge section (3) of a wind turbine blade (1), at least part of said section (3) being formed in a deformable material. The blade section (3) comprises one or more cavities (5) being in connection with or connectable to a fluid source in a way that allows fluid to stream from the fluid source to the cavity or cavities (5), so that the shape of the deformable trailing edge section (3) and thereby the camber of the blade cross-section (3) is changeable by the pressure of fluid in the cavity or cavities (5) with insignificant changes of the thickness and chord wise length of the deformable trailing edge section. Furthermore a wind turbine blade (1) is described, having at least one of such trailing edge section (s) (3) and to a system (11) for mounting a blade section (3) on a main blade (2) of a wind turbine. In addition a method of manufacturing a deformable trailing edge section (3) of a wind turbine blade (1) is disclosed.
    Type: Grant
    Filed: July 6, 2007
    Date of Patent: April 16, 2013
    Assignee: Danmarks Tekniske Universitet
    Inventors: Helge Aagaard Madsen, Flemming Rasmussen, Thomas Buhl, Morten Hartvig Hansen, Dan Christian Bak, Mac Gaunaa, Peter Bjørn Andersen
  • Patent number: 7632068
    Abstract: The present invention relates to a design concept by which the power, loads and/or stability of a wind turbine may be controlled by typically fast variation of the geometry of the blades using active geometry control (e.g. smart materials or by embedded mechanical actuators), or using passive geometry control (e.g. changes arising from loading and/or deformation of the blade) or by a combination of the two methods. The invention relates in particular to a wind turbine blade, a wind turbine and a method of controlling a wind turbine.
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: December 15, 2009
    Assignee: Technical University of Denmark
    Inventors: Dan Christian Bak, Thomas Buhl, Peter Fuglsang, Helge Aagaard Madsen, Flemming Rasmussen
  • Publication number: 20090290982
    Abstract: A deformable trailing edge section (3) of a wind turbine blade (1), at least part of said section (3) being formed in a deformable material. The blade section (3) comprises one or more cavities (5) being in connection with or connectable to a fluid source in a way that allows fluid to stream from the fluid source to the cavity or cavities (5), so that the shape of the deformable trailing edge section (3) and thereby the camber of the blade cross-section (3) is changeable by the pressure of fluid in the cavity or cavities (5) with insignificant changes of the thickness and chord wise length of the deformable trailing edge section. Furthermore a wind turbine blade (1) is described, having at least one of such trailing edge section (s) (3) and to a system (11) for mounting a blade section (3) on a main blade (2) of a wind turbine. In addition a method of manufacturing a deformable trailing edge section (3) of a wind turbine blade (1) is disclosed.
    Type: Application
    Filed: July 6, 2007
    Publication date: November 26, 2009
    Inventors: Helge Aagaard Madsen, Flemming Rasmussen, Thomas Buhl, Morten Hartvig Hansen, Dan Christian Bak, Mac Gaunaa, Peter Bjørn Andersen
  • Patent number: 6705838
    Abstract: The present invention relates in a broad aspect to a method for design and modification of airfoils useful for wind turbine applications, which airfoils possess smooth and stable characteristics in stall. These characteristics comprise: (1) No or very little tendency to double stall, (2) Insensitivity or little sensitivity of maximum lift to leading edge roughness, (3) High lift-drag ratio just before maximum lift, (4) Small variations of the aerodynamic loads in stall and (5) Sufficient aerodynamic damping to suppress blade vibrations in stall. The invention further relates to blades and/or airfoil sections in general which posses smooth and stabile characteristics in stall. Also, it relates to a method of implementing the desired shape on an airfoil or a wind turbine blade.
    Type: Grant
    Filed: May 8, 2002
    Date of Patent: March 16, 2004
    Assignee: Forskningscenter Riso
    Inventors: Dan Christian Bak, Peter Fuglsang