Savonius wind turbine ratios
OwnerMark Daniel Farbinventor
Life of this patent
Estimating the term…
Abstract
A Savonius wind turbine has been noted in the past to have the capability to perform more efficiently than other drag-type vertical axis turbines when built according to certain parameters. The previous literature has missed seeing the ratio of the shaft diameter to the available space for wind to pass through in the center as the crucial relationship on which other improvements in this type of turbine can be built. The chord diameter and overlap distance all depend on the size of the central shaft and its ratio to the inner endpoints of the overlapping semicircular blades. The ratios for maximal efficiency are presented here. These efficient ratios also depend for their execution on the turbine rotating at an ideal tip speed ratio.
Claims13
A vertical axis turbine, comprising a first blade and a second blade, each of which is semicircular in a horizontal plane for any cross-section along the height of the turbine, with a central shaft in the vertical direction, the first blade and the second blade each having concave sides that partially face each other, each semicircle of the first and second blades extends between an inner endpoint and an outer endpoint, and is characterized by a chord diameter c, referring to the distance between said inner endpoint and said outer endpoint,
- wherein said blades are spaced at an inner distance a extending along a virtual line from the inner endpoint of the semicircle of the first blade to the inner endpoint of the semicircle of the second blade and passing in a straight line through the shaft having a diameter of sd, wherein the inner distance a is 3 to 4 times the shaft diameter sd,
- wherein the chord diameter c is 6 to 7.2 times the shaft diameter sd.
A method of making a vertical axis turbine, the method comprising:
- providing a first blade and a second blade, each of which is semicircular in a horizontal plane for any cross-section along the height of the turbine, with a central shaft in the vertical direction, the first blade and the second blade each having concave sides that partially face each other, each semicircle of the first and second blades extends between an inner endpoint and an outer endpoint, and includes a chord diameter c, referring to the distance between said inner endpoint and said outer endpoint, wherein said blades are spaced at an inner distance a extending along a virtual line from the inner endpoint of the semicircle of the first blade to the inner endpoint of the semicircle of the second blade and passing in a straight line through the shaft having a diameter of sd,
- choosing a shaft diameter sd,
- making the inner distance a 3 to 4 times the shaft diameter sd, and
- making a chord diameter c of 6 to 7.2 times the shaft diameter sd.
Dependencies are inferred from the claim text.