Acoustic emissions verification testing of International Space Station experiment racks at the NASA Glenn Research Center Acoustical Testing Laboratory

Abstract

The Acoustical Testing Laboratory (ATL) at the NASA John H. Glenn Research Center (GRC) in Cleveland, OH, provides acoustic emission testing and noise control engineering services for a variety of specialized customers, particularly developers of equipment and science experiments manifested for NASA’s manned space missions. The ATL’s primary customer has been the Fluids and Combustion Facility (FCF), a multirack microgravity research facility being developed at GRC for the USA Laboratory Module of the International Space Station (ISS). Since opening in September 2000, ATL has conducted acoustic emission testing of components, subassemblies, and partially populated FCF engineering model racks. The culmination of this effort has been the acoustic emission verification tests on the FCF Combustion Integrated Rack (CIR) and Fluids Integrated Rack (FIR), employing a procedure that incorporates ISO 11201 (‘‘Acoustics–Noise emitted by machinery and equipment–Measurement of emission sound pressure levels at a work station and at other specified positions–Engineering method in an essentially free field over a reflecting plane’’). This paper will provide an overview of the test methodology, software, and hardware developed to perform the acoustic emission verification tests on the CIR and FIR flight racks and lessons learned from these tests.