Subsonic and Transonic Similarity Rules for Jet-Flapped Wings.
Abstract
Linear-subsonic and nonlinear-transonic similarity rules are derived for a finite-span jet-flapped wing with partial or full-span blowing. Although some subsonic rules previously have been published for jet-flapped wings, those presented herein are more general. The nonlinear transonic rules are new. The rules for both flow regimes employ a new jet-sheet compatibility condition that is second order relative to the jet-sheet internal flow and yields a jet-momentum coefficient similarity parameter differing from the conventional parameter in that it includes the effect of the jet-supply pressure ratio. The examples presented show that the second-order effect is significant only for conditions under which a convergent jet nozzle chokes at a relatively low free-stream Mach number, say, less than 0.5. The relation of the present rules to previously published rules for both blown and unblown wings is discussed briefly. The experimental data available for validation of the linear rules is rather sparse and is plagued with uncertainties regarding wind-tunnel interference corrections. Nevertheless, some comparisons with experiment are made and fair agreement is achieved. These comparisons revealed that camber-line effects associated with blowing could be significant in transonic applications. There is no experimental data of appropriate configurational simplicity and of sufficient generally in parametric variations to permit validation of the nonlinear rules. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1976
- Accession Number
- ADA033550
Entities
People
- Henry W. Woolard
Organizations
- Flight Dynamics Laboratory