Patent · US Expired

Actively controlled acoustic treatment panel

US5702230A · kind A · utility

19Cited by
18References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 29, 1996
Grant dateDec 30, 1997
Priority date
Expiry dateJan 29, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG10K2210/3227
  • WIPO fieldOther consumer goods
  • WIPO sectorOther fields

Abstract

An actively controlled acoustic treatment panel for suppressing noise in a gas turbine engine nacelle including a backsheet formed by a planar matrix of adjacent individually controllable elements, where each of the controllable elements has a transducer and a honeycomb cell enclosing the transducer. A facesheet is also bonded to the controllable elements. A plurality of sensors are positioned within the acoustic treatment panel for sensing acoustic pressure of the noise propagated against the facesheet. A driver is provided for electrically driving each of the transducers to effect displacement thereof in a direction substantially perpendicular to the facesheet. Circuitry is also operatively connected to the pressure sensors and the driver for controlling velocity magnitude and phase of the transducers during displacement, wherein a resulting acoustic impedance at the facesheet achieves a desired acoustic impedance boundary condition at the nacelle. The transducer is further made up of an inner lamination layer, an outer lamination layer, and a piezoelectric membrane positioned between the inner and outer lamination layers, wherein a plurality of aligned openings are provided in t…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.