In August 2001 the prototype (with a single wing) showed thrust forces on a test stand.
The advantages of such systems is the very precise and instantaneous control over the thrust force.
The lower thrust force results in a burr-less hole when drilling in metals.
Valveless engines produce thrust forces in two distinct but synchronized mass acceleration events per cycle, rather than just one.
This deflector redirects thrust forces forward to provide reverse thrust.
This keeps the significant thrust forces from impacting fragile tunnel walls.
This would violate the conservation of momentum if the wind turbine was not applying a thrust force on the flow.
This thrust force manifests itself through the pressure drop across the rotor.
The pressure difference from the front to back causes the thrust force.
The momentum lost in the turbine is balanced by the thrust force.