Accession Number : ADA318705

Title :   Nonlinear Aeroprediction Methodology for Roll Positions 0 and 45 Degrees,

Corporate Author : NAVAL SURFACE WEAPONS CENTER DAHLGREN VA

Personal Author(s) : Moore, F. G. ; McInville, R. M.

PDF Url : ADA318705

Report Date : 1996

Pagination or Media Count : 17

Abstract : The Naval Surface Warfare Center, Dahlgren Division Aeroprediction Code has been extended to the roll position of 45 deg (or fms in cross or orientation). New technology developed and discussed in this paper includes: wing-body and body-wing interference factors for this roll orientation and to angles of attack of 90 deg; approximate methods to estimate wing-alone center of pressure shift at high angles of attack and 45 deg roll position; and 'fm choking' at high Mach number. This new technology allows aerodynamics to be estimated with average accuracy levels of plus or minus 10 percent on normal and axial force coefficients and plus or minus 4 percent of body length on center of pressure. Exceptions to this are at subsonic Mach number and high angle of attack where wind tunnel sting interference effects are present, and at high Mach number and angle of attack where internal shock interactions from a forward fm onto an aft-mounted fm are present. Results are presented for several wing-body and wing-body-tail configurations at various Mach numbers and angles of attack to support this average accuracy level conclusion.

Descriptors :   *ROLL, *AERODYNAMIC CHARACTERISTICS, POSITION(LOCATION), FORWARD AREAS, INTERACTIONS, FREQUENCY MODULATION, ORIENTATION(DIRECTION), ACCURACY, ANGLE OF ATTACK, APPROXIMATION(MATHEMATICS), COEFFICIENTS, LENGTH, CONFIGURATIONS, SHOCK, SHIFTING, PRESSURE, AXES, SUBSONIC CHARACTERISTICS, MOUNTS, MACH NUMBER, WING BODY CONFIGURATIONS, FORCE(MECHANICS), HIGH ANGLES, TAILS(AIRCRAFT).

Subject Categories : Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE