Nick, i was refering to the system ability to respond to transients. Angular momentum is mwr^2 or mvr, so that increasing radius momentarily drops the aerofoil speed. It requires a torque increase just until tip speed is recovered. My concern is that this introduces lead/lag modes, if the rotor radius is being continously adjusted. For steady state, or long time constant inputs, your analysis is spot on.
I'm actually slightly confused here. Isn't the rotor normally sized as large as practical for a given machine, to keep disk loading down? Why would a designer want to reduce the rotor diam for a given machine on the fly? The only reason i can think of is for reduced landing area, say for ship ops.
Henshaw, i though the variable camber design was for fixed chord? This way you allow the "clean rotor" to run near Ct/sigma of 0.125, but with the option of deploying flaps quickly for increasing lift. Rotor figure of merit efficiency would be reduced in the manouvre, but this is a temporary state. I was trying to think of a relatively simple mechanism which would improve the rotor efficiency without sacrificing the manouvre performance. Increasing chord to maintain constant Ct/sigma is a good future development, but basics first...
Last edited by Graviman; 23rd Sep 2007 at 13:44.
Reason: Clarification only.