The recently observed phenomenon of high noise radiation from the side edges of flaps in flow is investigated by way of a simple two-dimensional model problem. The model is based upon a physical picture of boundary layer vorticity being swept around the edge by spanwise flow on the flap. The model problem is developed and solved and the resulting noise radiation calculated. Further, a mathematical condition for the vortex to be captured by the potential flow and swept around the edge is derived. The results show that the sound generation depends strongly upon the strength of the vorticity and distance from the edge and that it can be more intense than the more common trailing edge noise source in agreement with the experimental observations. (Stoehr)
Noise radiation from the side edges of flaps
Laermabstrahlung von den Seitenkanten von Klappen
AIAA Journal ; 18 , 5 ; 549-552
1980
4 Seiten, 4 Bilder, 11 Quellen
Aufsatz (Zeitschrift)
Englisch
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