ASA 127th Meeting M.I.T. 1994 June 6-10

3aED4. Behavior of an air jet interacting with a Helmholtz resonator.

Jason A. Kottke

James P. Cottingham

Phys. Dept., Coe College, Cedar Rapids, IA 52402

The internal spectrum of a Helmholtz resonator excited by an air jet was studied as a function of jet speed for a variety of jet parameters. Special attention was given to the relation between jet speed and amplitude of the Helmholtz mode, which shows a pattern of characteristic ``domains'' first reported by Khosropour and Millet [J. Acoust. Soc. Am. 88, 1211--1221 (1990)]. The effects of variation of air-jet length on major features of these domains were studied. The deduced behavior of the air jet was compared with previous models, in particular that of Fletcher and Thwaites [Acustica 42, 323--334 (1979)]. Good agreement with the predictions of this model was discovered except at high jet flow rates.