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Jan24-10, 06:26 AM
P: 45
Quote Quote by Swedpat View Post
Thanks for your reply!

Interesting things you share, though it may be a bit over my physical knowledge to count out these details. But according to what you say and the values you show the efficiency of a propeller is very depending of the right size and pitch for the intended speed.
For slow (10-30 km/h) moving cars, bicycles driven with propeller beter, of corse, larger propeler, than smaller propeller and beter more blades propeller, than less blades propeller, but with higher rpm if you want bigest eficienty (for example for bicycle driven with propeller if we want speed 20 km/h need about 0.6 meter propeller with 4 blades and 2000 rpm propeller rotating speed; need about 5 kg thrust to pull bicycle, who weight with rider about 80 Kg).
Quote Quote by Swedpat View Post
About the efficiency, did I got it right that this is the same thing as the percentual thrust compared to wheel drive at the actual speed (and assuming wheel drive had 100% efficiency)?
I, how is in reallity, do not known.