Method for improving efficiency of boat propellers comprises modifying blades over part of perimeter to create deflectors on intrados

摘要

The methods consists of modifying the end of the propeller blades (2) over a zone between 1/3 and 1/6 of their total perimeter so as to create deflectors (10) on the intrados which are able to be pulled down downstream of the propeller in a direction parallel to the rotational axis. The water flow is directed radially by the centrifugal force caused by the rotation of the propeller. An Independent claim is included for a modified propeller.