Inventors:
Michael J. Burke - Annapolis MD
George W. Tye - Sykesville MD
Assignee:
Noise Cancellation Technologies - Linthicum MD
International Classification:
G10K 1116
Abstract:
An elliptically shaped flow modulator in a duct with a circular cross section is used to produce a time varying head loss in a steady fluid flow in the duct, which results in an unsteady volume velocity at the end of the duct which radiates an acoustic field; the flow modulator can be used in place of a conventional acoustic source in an active noise control system.