Acoustic Test Facility Capabilities at Gulfstream Aerospace

摘要

Gulfstream Aerospace Corporation (GAC) owns and operates an Acoustic Test Facility (ATF) in Savannah, GA. The ATF consists of a Reverberation Chamber, Hemi-Anechoic Chamber, and a Control Room. Types of testing conducted in the ATF include Transmission Loss, Sound Power, and Vibration testing. In addition to accommodating typical types of acoustic testing, the ATF has some unique capabilities. The ATF can be used to conduct testing at cold temperatures representative of up to 45,000 ft flight altitude, while simultaneously taking Transmission Loss measurements of the chilled test sample. Additionally, the ATF has the capability of conducting Transmission Loss testing of a full mockup of the aircraft sidewall, including a section of fuselage, all the thermal/acoustic materials up to and including the interior decorative panel. A sound source capable of very high amplitudes at high frequencies is required to obtain good measurements from testing multiple wall systems such as this. The ATF uses a sound source that can produce 140dB SPL at frequencies above 1000Hz. Another challenge for measuring high Transmission Loss systems is flanking. Extreme care must be taken to ensure that the surrounding structure produces significantly more Transmission Loss than the test sample. The ATF utilizes a combination of a high amplitude noise source, an effective barrier, and good sealing techniques to ensure that GAC can measure Transmission Loss in excess of 120dB.