Vibroacoustic Modeling Study of the Delta II 10-Foot Composite Fairing

Abstract

The Boundary Element Method (BEM) has seen increasing use in the space industry to predict vibroacoustic responses of spacecraft and launch vehicle structures. The BEM application is used in the low-frequency regime where Statistical Energy Analysis (SEA) is usually inapplicable. This paper documents a vibroacoustic study of the Delta II 10-ft composite fairing using BEM and SEA. The fairing vibration and internal acoustic levels are predicted. The BEM and SEA predictions are compared with data from the Delta II 10-ft composite fairing acoustic test. The relative accuracy of the BEM and SEA methods in various frequency ranges is discussed. In addition, computer system requirements and lessons learned from BEM and SEA modeling are presented.