Acoustic intensity measurement apparatus and method including probe having ambient noise shield

• US 4,463,453 A
• Filed: 12/22/1981
• Issued: 07/31/1984
• Est. Priority Date: 12/22/1981
• Status: Expired due to Fees

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Cohen, Robert L., Dalan, Geir A.
• Primary Examiner(s): Farley, Richard A.
• Application Number:
  US06/333,546
• Time in Patent Office: 952 Days
• Field of Search: 381/87, 381/88, 381/91, 381/92, 181/198, 367/135, 367/140, 367/151, 367/910, 73/579, 73/583, 73/587, 73/591, 73/658, 73/659, 73/661, 73/802, 73/646, 73/647, 73/648
• US Class Current: 367/135
• CPC Class Codes: G01H 3/12 by electric means G01H3/14 takes precedence
• CPC Class Codes: Y10S 367/91 Portable sonar devices

Abstract

Acoustic intensity measuring apparatus for determining sound energy intensity utilizing a probe having a pair of microphones and an associated ambient noise shield.

Claims

1. An acoustic intensity probe comprising in combination:

an outer housing having an open end, said housing having a central axis and a sound absorbing chamber within said outer housing; and

,

a pair of microphones disposed along said central axis at the open end of said outer housing.

2. In an acoustical testing apparatus, a probe including:

a pair of microphones; and

an acoustic intensity probe ambient noise shield enclosing said pair of microphones so that the dipole directivity of said probe attenuates the tangential component of sound radiation from a radiating source.

3. In the method of measuring sound intensity from a noise source:

disposing a pair of microphones along the central axis of an open ended housing;

disposing the open end of said open ended housing a predetermined distance from a flat radiating surface; and

then,

coupling said microphone pair to a digital Fourier analyzer for measuring the sound intensity from said flat radiating surface.

4. The method of measuring sound intensity from a flat-shaped panel noise source which includes the step of disposing a two-microphone housing a predetermined distance from said flat-shaped panel noise source so that sound leakage entering said two-microphone housing approaches a two-microphone pair disposed along a central axis of said two-microphone housing at a substantially tangential angle.