Patent Application
20210207578
Reducing fluid density at certain locations about Savonius rotors and vehicles can improve the performance of these structures by reducing fluid friction through the medium through which these structures are made to travel.
A circular cylinder made to spin in a fluid made to move crosswise to its axis of spin is known as a Magnus Rotor. This device is made to produce a fluid dynamic side force, perpendicular to both the fluid direction and the axis of spin. For example, a cylinder made to spin on its central axis in a wind, with that axis horizontal, made to spin so its lower surface is made to move against the wind, produces a lifting force. This force has been studied both theoretically and experimentally,
and was found to be about ten times as strong as the corresponding force produced by an airfoil when compared at equal projected area, wind speed, and air density, if the cylinder were spun fast enough. The power input for a Magnus Rotor is found by using the formula P=the coefficient of friction times the cube of the angular velocity times pi times the radius to the fourth power times the length. (from USDOE Grant Report DOE/R6/10969)
Another relevant technology to this invention is the Flexible Shaft, which is made out of layers of high tensile wire wound over each other at opposing pitch angles. When torque is applies to the flexible shaft, the wire layers are made to expand or contract depending on the direction of rotation. If the torque causes the outer layer to contract, the layer underneath will be made to expand. This creates a dynamic interference between the layers of the shaft resulting in high torsional stiffness-approximately 100 times greater than the sum of the individual layers acting alone. There are many patents for this technology, eg. U.S. Pat. No. 1,586,750 and so on.
While the Flettner patent (Re18,122) shows many variations of a Magnus Rotor, all these variants show the rotor only rooted on one end. This complicates the stability of the rotor, for example dealing with the presence of gyroscopic forces.
In a first preferred embodiment, at least two long and thin magnus rotors are placed vertically on the leading surface of a Savonius Rotors spinning in opposite directions so that oncoming air is speeded up, creating a low pressure volume of air, drawing the Savonius Rotor forward (ie. creating a lift force) and lowering air resistance.
In a second preferred embodiment, a series of magnus rotors in the form of flexible shafts are spread over a curved surface to speed up the flow of fluid next to the surface and thereby create a low pressure zone so the surface of, for instance, a racing car or a helical Savonius rotor blade may be accelerated more easily through the atmosphere around it.
Turning to
There is shown a magnus rotor 4 affixed on either end to brackets 19,20, affixed in their turn to the rotor blade 1 or 3. The magnus rotor itself has no end pieces for reasons of efficiency, as was demonstrated in the experimental work recorded in USDOE Grant Report DE-FG46-79R610969. Motor 9 provides the power to operate magnus rotor 4.
In operation, Savonius blades are made to rotate about shaft 2 by wind. At the same time motors 10 are made to revolve magnus rotors 4, 4a, 5,5a in directions away from the centerlines of blades 1,3 at high rates of speed. This action produces a relative vacuum at areas A,B as well as lowering the air pressure at the outer surfaces of blades 1,3. Thus, more torque is produced on shaft 2.
Turning to
From the above descriptions it is apparent that the preferred embodiments achieve the object of the invention. Alternative embodiments and various depictions of the present embodiments will be apparent to those skilled in the relevant arts.
