Accession Number : ADA336099

Title :   Analysis of Limit Cycle Oscillation/Transonic High Alpha Flow Visualization

Descriptive Note : Final technical rept. 30 Sep 94-30 Sep 97

Corporate Author : LOCKHEED MARTIN CORP FT WORTH TX TACTICAL AIRCRAFT SYSTEMS

Personal Author(s) : Cunningham, Atlee M., Jr. ; Geurts, Evert G.

PDF Url : ADA336099

Report Date : 11 DEC 1997

Pagination or Media Count : 252

Abstract : A flow visualization test was conducted with the simple straked wing in August, 1996 (at the National Aerospace Laboratory NLR, The Netherlands), for the purpose of obtaining flow visualization data to compliment the pressure and force data base generated in earlier tests of the same configuration. This tests was conducted in two parts to examine the flow field characteristics (1) at high alpha conditions that involve vortices, shocks, and separated flows, and (2) at low alpha condition typical of transonic LCO flows with and without tip stores. Laser light sheet/water vapor techniques were used to illuminate the flows, and video recording was used to obtain the data. Both low and high speed video cameras were used to examine spanwise and streamwise laser sheet positions. In addition, under NLR funding, some preliminary particle image velocimetry (PIV) data were obtained at M = 0.225 and 0.6, as well as some pulsed laser flow visualization (9 nano-sec pulse) at M = 0.9. Correlation was performed between the flow visualization data from this test and the pressure/force data obtained in 1992 on the same configuration.

Descriptors :   *FLOW VISUALIZATION, *TRANSONIC FLOW, DATA BASES, PULSED LASERS, VORTICES, AEROELASTICITY, FLOW FIELDS, WIND TUNNEL TESTS, UNSTEADY FLOW, FLOW SEPARATION, PRESSURE DISTRIBUTION, STRAKES, WING TIPS, STEADY FLOW, TRANSONIC CHARACTERISTICS.

Subject Categories : Aerodynamics
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE