Propeller efficiency versus efficiency losses.
Propeller efficiency versus efficiency losses.
(OP)
When you say that a propeller has an efficiency of 51%, does it then mean that the efficiency losses with respect to the ideal propeller are 49%?
My answer would be NO!
Why? Because the ideal propeller will have an efficiency lower than 100%! Therefore the losses with respect to the ideal propeller will be less than 49%.
Right?





RE: Propeller efficiency versus efficiency losses.
Regards
Dave
RE: Propeller efficiency versus efficiency losses.
If defined as follows:
Overall Propeller Efficiency = Useful Power / PowerIn = (Useful Power / PowerOut)* (PowerOut / PowerIn)
Then an ideal propeller has efficiency < 100%, because Useful Power < PowerOut.
(Useful power is the Thrust * Airspeed)
RE: Propeller efficiency versus efficiency losses.
RE: Propeller efficiency versus efficiency losses.
altitude affects things in a really complicated manner (write that in your answer and see how far you get !). altitude typically reduces the power output of the engine (as you reduce the amount of O2 in the charge air volume). supercharging helps maintain sealevel performance at altitude. the V in the power equation above is true airspeed; the Thrust generated by the propeller (T = Ct*q*A) is, i think, relatively independent of altitude.
RE: Propeller efficiency versus efficiency losses.