NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Control of leading edge vortex breakdown by blowingAn investigation into the effects of using a jet of air to control the vortex breakdown position on a 70 degree delta wing is presented. The specific objectives focused on optimizing the blowing positions in terms of maximum lift increments obtained for minimum blowing rates. The tests were conducted at chord Reynolds numbers of 150,000, 200,000, and 250,000 at angles of incidence of 30 and 35 degrees. Visualization and force data is presented to show the effect of the jet on the wing aerodynamic characteristics. The results indicate a jet position located at and aligned parallel to the leading edge to be the optimum. Nearness to the apex and tangency to the upper surface were also crucial factors. The influence of the jet on the leading edge vortex structure was examined using laser Doppler anemometry. Velocity surveys through the vortex showed that at high blowing rates the parallel velocity in the outer swirling region of the vortex increased and the normal velocity decreased. This resulted in a decrease in the swirling angle in the outer region. The peak core velocity was reduced and the vortex breakdown was delayed.
Document ID
19880035144
Document Type
Conference Paper
Authors
Visser, K. D. (Notre Dame Univ. IN, United States)
Iwanski, K. P. (Notre Dame Univ. IN, United States)
Nelson, R. C. (Notre Dame Univ. IN, United States)
Ng, T. T. (Notre Dame, University IN, United States)
Date Acquired
August 13, 2013
Publication Date
January 1, 1988
Subject Category
AERODYNAMICS
Report/Patent Number
AIAA PAPER 88-0504
Funding Number(s)
CONTRACT_GRANT: NCA2-162
Distribution Limits
Public
Copyright
Other