Read on Twitter
Let's talk about the Magnus Effect & its application.
If a disc/cylinder is spinning in an airstream, it produces force perpendicular to both direction of spin & airstream.
Derived from Newton's 3rd law, Isaac postulated it from watching tennis matches at Cambridge, 1672.
If a disc/cylinder is spinning in an airstream, it produces force perpendicular to both direction of spin & airstream.
Derived from Newton's 3rd law, Isaac postulated it from watching tennis matches at Cambridge, 1672.
Magnus effect comes from differential pressures created by the objects spin.
It's the reason topspin causes baseballs to sink in flight, or bottomspin makes tennis balls float above the arc of their motion. The rate of spin produces lift, or drag: vectored force.
It's the reason topspin causes baseballs to sink in flight, or bottomspin makes tennis balls float above the arc of their motion. The rate of spin produces lift, or drag: vectored force.
Could we take that and harness it?
German engineer Anton Flettner (1885-1961) experimented with using spinning cylinders to generate lift or motive force.
This is the Rotor ship E-Ship 1, with 2 Flettner sails that drag it through the air. It also has auxiliary sea propellers.
German engineer Anton Flettner (1885-1961) experimented with using spinning cylinders to generate lift or motive force.
This is the Rotor ship E-Ship 1, with 2 Flettner sails that drag it through the air. It also has auxiliary sea propellers.
This is the more remarkable application: the least likely airplane ever built, the Plymouth A-A-2004, built 1930 in Long Island Sound.
It used spinning Flettner rotors instead of wings to generate lift, and a propeller to provide forward motion.
It used spinning Flettner rotors instead of wings to generate lift, and a propeller to provide forward motion.
The obvious design flaw: it's incapable of passive gliding. If the rotors stop rotating, it falls like a rock, but there are accounts of short flights.
This image is of the Butler Ames Aerocycle, which was built & tested 1910, but there aren't records of successful flights.
This image is of the Butler Ames Aerocycle, which was built & tested 1910, but there aren't records of successful flights.
The same principle can be applied to power-generating wind turbines. You spin these cylinders, and regardless of wind direction, there will be a strong force driving an axle to generate power.
The advantage is the cross-section is much more robust than long propeller blades.
The advantage is the cross-section is much more robust than long propeller blades.
'Typhoon generators' like this one are already deployed in Japan & use Magnus Effect to generate power even in typhoon strength winds, or under conditions of rapid wind directional change.
So, in summary, Magnus Effect generates invisible force from spinning cylinders in an airstream.
The applications are in understanding the motion of projectiles from baseballs to cruise missiles.
It can be used in place of a sail or a wing or a propeller.
The applications are in understanding the motion of projectiles from baseballs to cruise missiles.
It can be used in place of a sail or a wing or a propeller.