Numerical Estimation of Sound Transmission Loss in Launch Vehicle Payload Fairing

Abstract

Coupled acoustic-structural analysis of a typical launch vehicle composite payload faring is carried out, and results are validated with experimental data. Depending on the frequency range of interest, prediction of vibro-acoustic behavior of a structure is usually done using the finite element method, boundary element method or through statistical energy analysis. The present study focuses on low frequency dynamic behavior of a composite payload fairing structure using both coupled and uncoupled vibroacoustic finite element models up to 710 Hz. A vibroacoustic model, characterizing the interaction between the fairing structure, air cavity, and satellite, is developed. The external sound pressure levels specified for the payload fairing's acoustic test are considered as external loads for the analysis. Analysis methodology is validated by comparing the interior noise levels with those obtained from full scale Acoustic tests conducted in a reverberation chamber. The present approach has application in the design and optimization of acoustic control mechanisms at lower frequencies.

Study of Influential Factors of the Vibration Modal of the Rocket Equipment Bay and Structural Improvement Based on Finite Element Analysis

“…Zhang and Jiang [15] simulated the flight response of a rocket sled by using finite element coupling mechanical analysis. Chandana et al [16] analyzed six mode shapes of the launch vehicle payload fairing structure by finite element analysis.…”