Noise reduction of a composite cylinder subjected to random acoustic excitationInterior and exterior noise measurements were conducted on a stiffened composite floor-equipped cylinder, with and without an interior trim installed. Noise reduction was obtained for the case of random acoustic excitation in a diffuse field; the frequency range of interest was 100-800-Hz one-third octave bands. The measured data were compared with noise reduction predictions from the Propeller Aircraft Interior Noise (PAIN) program and from a statistical energy analysis. Structural model parameters were not predicted well by the PAIN program for the given input parameters; this resulted in incorrect noise reduction predictions for the lower one-third octave bands where the power flow into the interior of the cylinder was predicted on a mode-per-mode basis.
Document ID
19890046337
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Grosveld, Ferdinand W. (NASA Langley Research Center Hampton, VA, United States)
Beyer, T. (NASA Langley Research Center; Planning Research Corp. Hampton, VA, United States)