LABORATORY INVESTIGATION OF ATMOSPHERIC EFFECTS ON VORTEX WAKES

LABORATORY EXPERIMENTS CONDUCTED IN A STRATIFIED TOW TANK ARE PROPOSED TO CHARACTERIZE VORTEX WAKES UNDER THE INFLUENCE OF ATOMOSPHERIC DISTURBANCE. FLOW RESEARCH HAS DEVELOPED INNOVATIVE TECHNIQUES FOR STRATIFYING THE FLUID IN THE TANK, GENERATING A CURRENT SHEAR AND CREATING AMBIENTTURBULENCE WITH GOOD CONTROL. SUCH CAPABILITIES WOULD FACILITATE THE ISOLATION OF THE EFFECTS OF THE DISTURBANCE S ON THE VORTEX WAKES. TO DEMONSTRATE THE FEASIBILITY OF THEA TOWED WING (NACA 0012) AND BY A TWO-DIMENSIONAL VORTEX GENERATOR; THE LATTER WILL ONLY BE USED TO STUDY THE CROSS-SSHEAR EFFECTS. A SPECIAL MOUNT, USING THREE 0.008 CM DIA. WIRES TO SUSPEND THE WING MODEL, WILL BE USED TO ELIMINATE CONTAMINATION OF THE VORTEX WAKES BY THE WAKE OF A STRUT OR STING. VISUALIZATION EXPERIMENTS, USING FLUORESCENT DYE TO TRACK THE TRAILING VOTRTICIES AND DIFFERENT LIGHTING CON- FIGURATIONS, WILL BE CONDUCTED TO VISUALIZE THE VORTEX WAKESFROM SEVERAL PERSPECTIVES. QUALITATIVE AND QUANTITATIVE INFORMATION REGARDING THE EVALUATION OF THE VORTEX WAKES UNDER THE INFLUENCE OF THE DISTURBANCES WILL BE DERIVED FROMTHE VISUAL RESULTS. THE AMBIENT CONDITIONS WILL BE MEASURED WITH PROBE SENSORS, SUCH AS HOT-FILM AND CONDUCTIVITY PROBE,AND BY OPTICAL MEANS.