Last modified: 2013-04-19
Abstract
The Structural Acoustics Loads and Transmission (SALT) laboratory [1] at the NASA Langley Research Center is comprised of an anechoic chamber and a reverberant chamber, and may act as a transmission loss suite when test articles are mounted in a window connecting the two chambers. In the latter configuration, the reverberant chamber acts as the noise source side and the anechoic chamber as the receiver side. In either configuration, the noise generation system was previously shown to achieve a maximum overall sound pressure level of 141 dB [2]. This is considered to be marginally adequate for generating sound pressure levels typically required for launch vehicle payload qualification testing. Recent enhancements to the noise generation system increased the maximum overall sound pressure level to 154 dB. This paper will document the acoustic performance of the enhanced noise generation system for a variety of relevant test spectra. Additionally, it will demonstrate the capability of the SALT laboratory to conduct transmission loss and absorption testing in accordance with ASTM [3] and ISO [4] standards, respectively. Results from a transmission loss test of a new hybrid wing-body fuselage concept will be shown to demonstrate that capability [5].