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Cyclorotor
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Cyclorotor
A cyclorotor, cycloidal rotor, cycloidal propeller or cyclogiro, is a fluid propulsion device that converts shaft power into the acceleration of a fluid using a rotating axis perpendicular to the direction of fluid motion. It uses several blades with a spanwise axis parallel to the axis of rotation and perpendicular to the direction of fluid motion. These blades are cyclically pitched twice per revolution to produce force (thrust or lift) in any direction normal to the axis of rotation. Cyclorotors are used for propulsion, lift, and control on air and water vehicles. An aircraft using cyclorotors as the primary source of lift, propulsion, and control is known as a cyclogyro or cyclocopter. A unique aspect is that it can change the magnitude and direction of thrust without the need of tilting any aircraft structures. The patented application, used on ships with particular actuation mechanisms both mechanical or hydraulic, is a Voith Schneider Propeller.
The blades revolve around the central axis while individually cycling back and forth to engage (creating driving force) and disengage (to avoid creating drag). By adjusting their angle-of-attack they maximize the net force. This joint action generates a higher thrust at low speed than any other propeller design.
In aircraft hover, the blades adjust to a positive pitch (sharp edge facing outward from the centre of the rotor) on the upper half of their revolution and a negative pitch (sharp edge inward) over the lower half inducing a net upward aerodynamic force and opposite fluid downwash. By varying the phase of this pitch the force can be shifted to any angle. Increasing the pitching kinematics amplitude magnifies thrust.
The cyclorotor propeller emerged in Russian aeronautics. Sverchkov's "Samoljot" (St. Petersburg, 1909) or "wheel orthopter" is the first vehicle thought to have used this system. Its scheme came near to cyclogiro, but is difficult to precisely classify. It had three flat surfaces and a rudder; the rear edge of one surface could be bent, replacing the action of an elevator. Lift and thrust had to be created by paddle wheels consisting of 12 blades, set in pairs at a 120° angle. The blades were concave. The angle of incidence was controlled by eccentrics and springs.
At the bottom of the craft a 10 horsepower engine was arranged. Transmission was by belt. The empty weight was about 200 kg. It was constructed by military engineer E.P. Sverchkov under the Main Engineering Agency. It was demonstrated at the Newest Inventions Exhibition and won a medal. However, it could not pass preliminary flight tests.
In 1914, Russian inventor and scientist A.N. Lodygin proposed a cyclogiro-like aircraft, similar to Samoljot, but the project was not carried out.
In 1933, Adolf Rohrbach experimented in Germany with a paddle wheel wing arrangement. Oscillating winglets cycled from positive to negative angles of attack during each revolution, and their eccentric mounting could, in theory, produce nearly any combination of horizontal and vertical forces. The DVL evaluated Rohrbach's design, but the aviation journals of the time cast doubt on the design preventing funding, even with a proposal as a Luftwaffe transport aircraft. No evidence indicates that this design was ever built. Platt in the US designed by 1933 his own independent Cyclogyro, based on Rohrbach's work. His arrangement was awarded a US patent (one of many similar patents), and underwent extensive wind-tunnel testing at MIT in 1927. Despite this, Platt's aircraft was never built.
The first functional design was developed at Voith in the 1930s. Its origins date to the decision of the Voith company to focus on turbine transmission gear assemblies. The Voight propeller was invented by Ernst Schneider and enhanced by Voith. It was launched as the Voith-Schneider Propeller (VSP) for commercial marine vessels. It significantly improved ship manoeuvrability as demonstrated in sea trials on the test boat Torqueo, in 1937. The first Voith Schneider Propellers were put to work in the canals of Venice, Italy. During the 1937 World Fair in Paris, Voith was awarded the grand prize – three times – for its propellers and turbo-transmissions. A year later, two of Paris' fire-fighting boats started operating with the system.
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Cyclorotor AI simulator
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Cyclorotor
A cyclorotor, cycloidal rotor, cycloidal propeller or cyclogiro, is a fluid propulsion device that converts shaft power into the acceleration of a fluid using a rotating axis perpendicular to the direction of fluid motion. It uses several blades with a spanwise axis parallel to the axis of rotation and perpendicular to the direction of fluid motion. These blades are cyclically pitched twice per revolution to produce force (thrust or lift) in any direction normal to the axis of rotation. Cyclorotors are used for propulsion, lift, and control on air and water vehicles. An aircraft using cyclorotors as the primary source of lift, propulsion, and control is known as a cyclogyro or cyclocopter. A unique aspect is that it can change the magnitude and direction of thrust without the need of tilting any aircraft structures. The patented application, used on ships with particular actuation mechanisms both mechanical or hydraulic, is a Voith Schneider Propeller.
The blades revolve around the central axis while individually cycling back and forth to engage (creating driving force) and disengage (to avoid creating drag). By adjusting their angle-of-attack they maximize the net force. This joint action generates a higher thrust at low speed than any other propeller design.
In aircraft hover, the blades adjust to a positive pitch (sharp edge facing outward from the centre of the rotor) on the upper half of their revolution and a negative pitch (sharp edge inward) over the lower half inducing a net upward aerodynamic force and opposite fluid downwash. By varying the phase of this pitch the force can be shifted to any angle. Increasing the pitching kinematics amplitude magnifies thrust.
The cyclorotor propeller emerged in Russian aeronautics. Sverchkov's "Samoljot" (St. Petersburg, 1909) or "wheel orthopter" is the first vehicle thought to have used this system. Its scheme came near to cyclogiro, but is difficult to precisely classify. It had three flat surfaces and a rudder; the rear edge of one surface could be bent, replacing the action of an elevator. Lift and thrust had to be created by paddle wheels consisting of 12 blades, set in pairs at a 120° angle. The blades were concave. The angle of incidence was controlled by eccentrics and springs.
At the bottom of the craft a 10 horsepower engine was arranged. Transmission was by belt. The empty weight was about 200 kg. It was constructed by military engineer E.P. Sverchkov under the Main Engineering Agency. It was demonstrated at the Newest Inventions Exhibition and won a medal. However, it could not pass preliminary flight tests.
In 1914, Russian inventor and scientist A.N. Lodygin proposed a cyclogiro-like aircraft, similar to Samoljot, but the project was not carried out.
In 1933, Adolf Rohrbach experimented in Germany with a paddle wheel wing arrangement. Oscillating winglets cycled from positive to negative angles of attack during each revolution, and their eccentric mounting could, in theory, produce nearly any combination of horizontal and vertical forces. The DVL evaluated Rohrbach's design, but the aviation journals of the time cast doubt on the design preventing funding, even with a proposal as a Luftwaffe transport aircraft. No evidence indicates that this design was ever built. Platt in the US designed by 1933 his own independent Cyclogyro, based on Rohrbach's work. His arrangement was awarded a US patent (one of many similar patents), and underwent extensive wind-tunnel testing at MIT in 1927. Despite this, Platt's aircraft was never built.
The first functional design was developed at Voith in the 1930s. Its origins date to the decision of the Voith company to focus on turbine transmission gear assemblies. The Voight propeller was invented by Ernst Schneider and enhanced by Voith. It was launched as the Voith-Schneider Propeller (VSP) for commercial marine vessels. It significantly improved ship manoeuvrability as demonstrated in sea trials on the test boat Torqueo, in 1937. The first Voith Schneider Propellers were put to work in the canals of Venice, Italy. During the 1937 World Fair in Paris, Voith was awarded the grand prize – three times – for its propellers and turbo-transmissions. A year later, two of Paris' fire-fighting boats started operating with the system.
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