Accession Number : ADP005885

Title :   Flow Visualization Study of Vortex Manipulation on Fighter Configurations at High Angles of Attack,

Corporate Author : EIDETICS INTERNATIONAL INC TORRANCE CA

Personal Author(s) : Malcolm, Gerald N. ; Skow, Sndrew M.

Report Date : JUN 1987

Pagination or Media Count : 19

Abstract : Experiments were performed in a flow visualization water tunnel on a generic fighter model to explore vortex manipulation as an effective means of aircraft control by altering the natural state of the forebody and LEX vortices in the medium-to-high-angle of attack range with either small surface modifiers or blowing jets. Specifically, the forebody vortex system was examined with the clean forebody, with forebody strakes, and with forebody surface blowing. LEX vortices were examined with a clean LEX, with small geometric modifications near the apex, and with surface blowing, both in upstream and downstream directions at various locations on the LEX surface. The interactive effects of forebody and LEX/wing vortices and their response to the various methods of control were also examined. Generally, it was concluded that the forebody vortices can be effectively controlled by either blowing or using strakes, but the effectiveness is very dependent on proper radial placement of the blowing port or strake. Geometric modifications and blowing at the LEX apex were not particularly effective in altering the trajectory of the LEX vortices or the burst points. Blowing aft of the mid-chord of the LEX was much more effective and could force the burst points to move forward significantly. Interactions between the forebody and LEX vortex systems were pronounced.

Descriptors :   *VORTICES, FLOW VISUALIZATION, ANGLE OF ATTACK, HIGH ANGLES, WATER TUNNELS, MODEL TESTS, JET FIGHTERS, AIRCRAFT MODELS, AERODYNAMIC CONTROL SURFACES, STRAKES, JET FLOW, LEADING EDGES, CONTROL, POSITION(LOCATION).

Subject Categories : Aerodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE