Prop Efficiency curves

LostinBoston · 03-06-2009, 03:57 PM

Does anyone have or know where to get prop efficiency curves for surface piercing props? Have any tests been done on them?
Thanks

Sean H · 03-06-2009, 04:16 PM

how are you trying to compare them? speed, rpm, slip ? probably way too many variables to have a constant curve to base anything off of.

bbladesprops · 03-10-2009, 06:28 PM

When you say efficiancy curves, what do you actually mean?

Props travel forward "x" amount of inches in 1 360 degree revolution. The propeller style and boat set up determine the amount of slip the props will have. Each boat is different so the efficiancy will vary also.

Brett

LostinBoston · 03-14-2009, 03:48 PM

Quote:

Originally Posted by bbladesprops

When you say efficiancy curves, what do you actually mean?

Props travel forward "x" amount of inches in 1 360 degree revolution. The propeller style and boat set up determine the amount of slip the props will have. Each boat is different so the efficiancy will vary also.

Brett

Yes I am very much aware of this. By effiency I mean puting the power to the water. How much SHP is needed for calculated or scaled (based on model tests) EHP.
It would be nice to compare slip rates to increase or decrease efficiency.

bbladesprops · 03-15-2009, 02:17 PM

I'm sorry, I'm still not clear on what you are ultimately looking for.

Non-progressively pitched cleavers are the most efficient type of propeller as far as transfereing HP to forward travel. However, this is on a limited application. Again, variables are so overwhelming, it is impossible to have any charted efficiency hold up for everybody.

Sorry if I'm not being of assistance.