Daryl M May

US Patent:

58334335, Nov 10, 1998

Filed:

Jan 7, 1997

Appl. No.:

8/779845

Inventors:

Daryl N. May - Cypress CA
Robert L. Chapkis - Rancho Palos Verdes CA

Assignee:

McDonnell Douglas Corporation - Huntington Beach CA

International Classification:

F04D 2938

US Classification:

415115

Abstract:

The present invention provides an apparatus and method for reducing noise caused by a rotating component. According to the invention, the apparatus comprises a plurality of emitters adapted to emit fluid under variable pressure in the vicinity of the rotating components such that unsteady forces on the rotating component are reduced or eliminated. Preferably, the apparatus includes at least one duct extending between the emitters and a high pressure area for directing the fluid under pressure. At least one flow controller is disposed along the duct to vary the pressure of the injected flow emitted from the emitters.