Quiet Shrouded Circulation Control Propeller.
Abstract
The patent application describes a propeller capable of generating high thrust at reduced noise levels, weight and drag. The propeller blades employ a tangential slot along the trailing edge of each propeller blade and circulation control blowing from the tangential slot over the trailing edge. Lift is generated by the coanda blowing. The lift is proportional to the momentum flow of the air out of the slot and is substantially independent of the rotational velocity. Additionally a circulation control shroud expands the thrusting slipstream of the propeller so that the shroud diffusion angle is increased and the average exit velocity is reduced, thereby increasing efficiency and reducing noise.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 11, 1974
- Accession Number
- ADD001177
Entities
People
- Robert M. Williams
Organizations
- United States Department of the Navy