Heel tank damper for floating structures

A method of mitigating dynamic responses from heel motion in a wind turbine platform capable of floating on a body of water and supporting a wind turbine thereon comprising:

• a wind turbine platform including:
• a keystone;
• a first pair bottom beams including two bottom beams connected to opposite sides of the keystone;
• a second pair of bottom beams including two bottom beams connected to opposite sides of the keystone, wherein the second pair of bottom beams has a longitudinal axis perpendicular to a longitudinal axis of the first pair of the bottom beams, wherein the keystone, the first pair of bottom beams, and the second pair of bottom beams define a foundation;
• wherein each bottom beam in the first and second pairs of bottom beams includes an outwardly extending portion at a distal end thereof;
• wherein the first and second pairs bottom beams define a foundation having a cruciform shape;
• wherein a U-shaped ballast conduit is one of mounted and formed within each of the first pair of bottom beams and the second pair of bottom beams, and extends between the outwardly extending portions of each bottom beam of each of the first and second pairs of bottom beams;
• and
• wherein the U-shaped ballast conduits have ballast water therein, the ballast water extending from the outwardly extending portions of each bottom beam of each of the first and second pairs of bottom beams, such that a volume of air is defined between a surface of the ballast water in each outwardly extending portion and an outwardly facing wall of each outwardly extending portion;
• and
• an internal damping element within the U-shaped ballast conduits;
• and
• a heel tank damper defined by the U-shaped ballast conduits and the internal damping element therein;
• the method including mitigating dynamic responses from heel motion by using the ballast water within the U-shaped ballast conduits as a mass element that is allowed to oscillate in a predetermined direction.

A wind turbine platform capable of floating on a body of water and supporting a wind turbine thereon in combination with a heel tank damper comprising:

• a wind turbine platform including:
• four connected bottom beams that extend radially outwardly from central point and define a foundation having a cruciform shape, wherein each bottom beam includes an outwardly extending portion at a distal end thereof;
• wherein an outwardly facing wall of each outwardly extending portion includes an opening that extends between an interior of the outwardly extending portion and the atmosphere outside of the outwardly extending portion;
• and
• a cross shaped wall having four legs that extend vertically between a lower wall of each beam and an upper wall of each beam, the distal ends of each of the four legs are spaced apart from distal end walls of each beam;
• and
• an integrated heel tank damper having multiple ballast conduits formed between the cross shaped wall and the walls of each beam, the multiple ballast conduits defining multiple fluid flow paths within the foundation.

A wind turbine platform capable of floating on a body of water and supporting a wind turbine thereon in combination with a heel tank damper comprising:

• a wind turbine platform including:
• a keystone;
• a first pair bottom beams including two bottom beams connected to opposite sides of the keystone;
• a second pair of bottom beams including two bottom beams connected to opposite sides of the keystone, wherein the second pair of bottom beams has a longitudinal axis perpendicular to a longitudinal axis of the first pair of the bottom beams,
• wherein the keystone, the first pair of bottom beams, and the second pair of bottom beams define a foundation having a cruciform shape;
• wherein each bottom beam in the first and second pairs of bottom beams includes an outwardly extending portion at a distal end thereof;
• wherein a U-shaped ballast conduit is one of mounted and formed within each of the first pair of bottom beams and the second pair of bottom beams, and extends between the outwardly extending portions of each bottom beam of each of the first and second pairs of bottom beams;
• and
• wherein the U-shaped ballast conduits have ballast water therein, the ballast water extending from the outwardly extending portions of each bottom beam of each of the first and second pairs of bottom beams, such that a volume of air is defined between a surface of the ballast water in each outwardly extending portion and an outwardly facing wall of each outwardly extending portion;
• an interior wall within each bottom beam that extends vertically between a lower wall and an upper wall of each bottom beam, and further extends longitudinally from distal end walls of each bottom beam to a vertically extending exterior wall of the keystone;
• and
• a cross-shaped wall within the keystone that extends vertically between a lower wall and an upper wall of the keystone, wherein each leg of the cross-shaped wall is longitudinally aligned with one of the interior walls of the bottom beams, and wherein the exterior walls and each of the legs of the cross-shaped wall of the keystone have vertically extending fluid flow openings formed therein, and define an internal damping element;
• and
• a heel tank damper system defined by the combination of the U-shaped ballast conduits and a plurality of fluid flow paths defined by the fluid flow openings in the walls of the keystone.

A semi-submersible wind turbine platform capable of floating on a body of water and supporting a wind turbine thereon in combination with a heel tank damper comprising:

• a semi-submersible wind turbine foundation including:
• a keystone;
• three bottom beams that extend radially outwardly from the keystone;
• a center column mounted to the keystone;
• three outer columns mounted at distal ends of the bottom beams;
• wherein a space within the center column, each outer column, the keystone and the bottom beam therebetween define three generally U-shaped ballast conduits;
• wherein the U-shaped ballast conduits have ballast water therein, the ballast water extending from the outwardly extending portions of each bottom beam of each of the first and second pairs of bottom beams, such that a volume of air is defined between a surface of the ballast water in each outwardly extending portion and an outwardly facing wall of each outwardly extending portion;
• and
• an internal damping element within the U-shaped ballast conduits;
• and
• a heel tank damper defined by the combination of the three U-shaped ballast conduits.