Apparatus for Improving the Overall Efficiency of a Marine Screw Propeller.
Abstract
Elongate slots are formed near the leading edges of propeller blades and a supply of polyethylene oxide is ejected through the slots to form a continuous sheet of the polymer flowing on the suction side surface in the region where about 70% of the thrust loading is distributed. The polymer changes the propeller's pressure distribution and increases its lift factor and efficiency. When ejected at a proper flow rate, frictional drag also is reduced. The slots are shaped channels having a particular depth, width and directional orientation that assures the continuity of the flowing sheet. To achieve the benefits, polymer concentration is maintained at a level capable of providing a trailing edge concentration of about 2-20 ppm. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 16, 1979
- Accession Number
- ADD006032
Entities
People
- August F. Kehman
Organizations
- United States Department of the Navy