Final Report,
Abstract
Preliminary performance studies are given of ducted and conventional ir propellers on hydro ki mer cr ft. The study includes the eff ct of off-design op ration on th choic of prop ller xces hrus for acceleration and op r ion over a rough sea are xample of off-design. Si ce the maintenance of low propell r nois is i portan , results are pres nted in terms of the res ltant blade tip speed as well as propell r rpm. n analysis i de of ducted and conventional air propellers for two hydroskimmers; one ia a 20 ton 70 knot craft, the other is a projected 125 kno craft. For both craft he ducted propeller ill have an appreciably smaller iameter than the conv tio al propeller. The ability to produce excess thrust in off-design is good for both types of propeller . It is shown that the drag increase due to operation over a rough sea can s arply reduce the attainable speed Propeller p rameters governing this condition are shown. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1962
- Accession Number
- AD0294626