Accession Number : ADA193018

Title :   Study of Three Dimensional Transonic Flow Separations.

Descriptive Note : Final rept. 1 Jul 81-30 Nov 87,

Corporate Author : AMF INC WHITE PLAINS NY*

Personal Author(s) : Owen, F K ; Orngard, G M ; McDevitt, T K ; Ambur, T A

PDF Url : ADA193018

Report Date : Apr 1988

Pagination or Media Count : 252

Abstract : An extensive wind tunnel study of flows with transonic swept separation zones and shock-boundary layer interactions on realistic stationary and spinning projectile test models was conducted in the NASA Ames 6- by- 6-ft. supersonic wind tunnel. These studies provide a detailed data base to assess the potential effects of symmetric and asymmetric three-dimensional transonic flow separations on projectile performance. A three-component laser velocimeter system, laser vapor screen, model balance and static and dynamic surface pressure gages were used to conduct detailed non-intrusive wind tunnel test measurements. This instrumentation was used to determine model forces and moments, surface pressure distributions and to explore the time-averaged and turbulent characteristics of the attached viscous and coiled free shear layers over ranges of angle of attack and transonic freestream Mach number. Flow field and aerodynamic static and dynamic surface pressure measurements were obtained on a stationary projectile model and normal and Magnus force and flow field measurements were made on a geometrically similar spinning model. A comparison of the two sets of three dimensional lee side flow field surveys shows that model spin produces significant changes in vortex position and strength which accounts for the measured destabilizing aerodynamic effects in the transonic test regime. Keywords: Transonic flow, Flow field measurements; Pressure measurement; Flow separation.

Descriptors :   *FLOW SEPARATION, *PROJECTILES, *SPINNING(MOTION), *TRANSONIC FLOW, *THREE DIMENSIONAL FLOW, AERODYNAMIC FORCES, AERODYNAMICS, BALANCE, DATA BASES, DYNAMIC PRESSURE, FLOW FIELDS, LASER VELOCIMETERS, MAGNUS EFFECT, MEASUREMENT, WIND TUNNEL MODELS, MOMENTS, POSITION(LOCATION), PRESSURE, PRESSURE DISTRIBUTION, PRESSURE GAGES, MEASUREMENT, STATICS, STATIONARY, SUPERSONIC WIND TUNNELS, SURFACE PROPERTIES, TEST METHODS, TURBULENCE, VORTICES, WIND TUNNELS, SYMMETRY, ASYMMETRY, SHOCK, BOUNDARY LAYER, INTERACTIONS, PROJECTILE TRAJECTORIES

Subject Categories : Ballistics
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE