AN EXPERIMENTAL INVESTIGATION OF NEW CONCEPTS IN EJECTOR THRUST AUGMENTATION FOR V/STOL.
Abstract
The basic concept involved in the investigation is the utilization of the Coanda effect in combination with an external cascade of airfoils. That combination served to achieve a more efficient rotation and amplification of the jet thrust vector as a result of both the large induced mass flow from the environment and the simultaneous high lift of the cascaded airfoils. The program objective was to establish optimal performance by systematic variation of the pertinent parameters. Experimental results showed a gain of 20% in augmented thrust compared to that of a simple Coanda cylinder. Since the observed mass flow through the airfoil cascade was small, in-house tests were performed with diffusion. The resultant increase in secondary mass flow produced a gain of 65% in thrust augmentation over the tests without diffusion despite large regions of flow separation in the diffuser. It appears highly probable that further large gains can result from precise diffuser design and boundary layer control in the diffuser. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1969
- Accession Number
- AD0691148
Entities
People
- Charles A. Smith
- Gordon L. Harris
- Morton Alperin