Accession Number : AD0717390

Title :   Experimental Investigation of Several Neutrally-Buoyant Bubble Generators for Aerodynamic Flow Visualization.

Descriptive Note : Technical rept. 1 May 68-31 Jan 69,

Corporate Author : SAGE ACTION INC ITHACA N Y

Personal Author(s) : Hale,R. W. ; Tan,P. ; Ordway,D. E.

Report Date : AUG 1969

Pagination or Media Count : 35

Abstract : Small, neutrally-buoyant soap bubbles have been used very effectively for mapping out low-speed aerodynamic flows, typically at velocities up to 50 fps. As opposed to conventional methods, such as smoke, they can accurately trace in detail turbulent and highly-sheared air motions. The objective of this investigation was to explore the feasibility of flow visualization with bubbles at velocities as high as 300-400 fps. The low-speed bubble generating device, or head, was tested first to supply the basis for designing a head for creating and implanting bubbles in higher-velocity airstreams. A prototype higher-speed head was then designed, fabricated and tested, both in-house and in a small Government wind tunnel. With this head, bubbles were accelerated to appreciably higher velocities than before and show promise of further improvements with continued development. Future requirements for bringing this technique to practical use are outlined and suggested approaches are proposed. (Author)

Descriptors :   (*FLOW VISUALIZATION, *BUBBLES), SOAPS, HELIUM, VELOCITY, FEASIBILITY STUDIES, AIRFOILS, PHOTOGRAPHY, FLOW FIELDS, TEST FACILITIES, WIND TUNNEL MODELS

Subject Categories : Test Facilities, Equipment and Methods
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE