Why do jet engines rotate in different directions?
Why do jet engines rotate in different directions?
A notable exception is the Rolls-Royce Pegasus engine for the Harrier jump jet. Stators between the rotating stages ensure that air flow inside the engine is mainly in axial direction, so aerodynamically a different rotation direction between two spools will make little difference.
Why are contra rotating jet engines more efficient?
This has the effect of making the compressor close to unstallable, which means you can run WAY higher compression ratios, thus increasing efficiency. Between the high pressure & low pressure exhaust stages, counter rotating blades extract more energy from the exhaust gases, thus delivering more torque to the bypass fan. For example the GE genx.
Why do all VTOL aircraft have counter rotating spools?
And of course, due to the issue of the precession, all VTOL aircraft have counter rotating spools, because it could prevent the aircraft starting to rotate slowly around the vertical axis. And no, this is not the same phenomenon as the helicopters have, by the main rotor torque.
Why are propellers used in a jet engine?
With propeller, contra-rotating propellers are the only way to stop rotation of the slip-stream. However jet engines have static guide vanes that stop the rotation almost as efficiently with a fraction of the complexity of actual contra-rotation. These are negligible compared to the aerodynamic forces in flight.
A notable exception is the Rolls-Royce Pegasus engine for the Harrier jump jet. Stators between the rotating stages ensure that air flow inside the engine is mainly in axial direction, so aerodynamically a different rotation direction between two spools will make little difference.
This has the effect of making the compressor close to unstallable, which means you can run WAY higher compression ratios, thus increasing efficiency. Between the high pressure & low pressure exhaust stages, counter rotating blades extract more energy from the exhaust gases, thus delivering more torque to the bypass fan. For example the GE genx.
What are the benefits of rotating Sewer jetting nozzles?
The Rotation of this sewer jetting nozzles adds extra agitation and surface cleaning. Rotating sewer nozzles have 3 sprays back for flushing out debris. Rotating duct cleaners have 2 sprays sideways for agitation at side walls.
What kind of pressure do you need for jetting?
Hard mineral deposits sometimes require jetting pressure as high as 10,000 psi. Perpendicular ports can be used on the Warthog head to maximize scale cleaning performance. Contact StoneAge, for optional jetting designs.