Propellor effeciency.

[jurgenscraft]

Is there a standard formuls I can use to calculate the effeciency of a propellor or how much does the propellor slip , eg a 13" pitch propellor should move 13" forward per revolution but for various reasons this is not the case, I have used math formula to calculate the theoritical top speed a propellor should generate at wot but hull shape and other factors contribute to the discprency between the two , theoritical and actual, actual is obtained by running the motor at wot and obtaining a speed reading via gps, I then calculate the percentage difference between the two and equate this to slip. eg 18% 0r 23% etc.where can I obtain these nautical formulas, Kind Regards William Wright

 

[Silvertip]

Re: Propellor effeciency.

Here ya go!<br /> http://www.rbbi.com/folders/prop/propcalc.htm

 

[jurgenscraft]

Re: Propellor effeciency.

Upinsmoke Thank you very much for your reply I have been to the web site provided and will brouse around later on and see what I can find. Kind regards William Wright.