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Reverberation chambers have been used for several years in aerospace industry to test the structural integrity of aerospace components subjected to acoustic loads. These experimental tests will incur high cost and workmanship. In order to reduce these costs and workmanship, numerical tool like finite element method can be implemented to simulate experimental condition for low frequency upto 250 Hz. Motivation of this work is to implement FEA technique to predict acoustic distribution and corresponding vibration response of the structure in a reverberation chamber. In this work, a simple Aluminium plate has been taken to study the vi-bro-acoustic response for experimentation and it is validated using FEA. The focus of this study is to find vibro-acoustic response of plate subjected to acoustic loads in a reverberation chamber. Experimentation and FEA technique has been carried out in three phases such as structural vibration, acoustic distribution, vibro-acoustic analysis of plate under the diffused sound field to get vibration response in GRMS and acoustic distribution in SPL. In modal analysis, the plate is suspended in free-free condition and carried out to get the natural frequency and mode shapes. Acoustic modal analysis is done to determine the natural frequency, standing waves in the closed chamber. In PSD and Harmonic analysis, input sound pressure levels (SPL) in octave band are converted into acoustic pressure to get the vibration and acoustic distribution. Results are validated in each phase with experimental results. An obtained result from PSD analysis was found to be 5% difference compared to experimental results. SPL distribution results for 63 and 125 Hz are within +/-2 dB compared to experimental results, which is in the permissible range of +/-3 dB. Maximum of 14.5% difference obtained for 125 Hz and 8% for 250 Hz compared to experiment are in acceptable range for vibration response of plate. Acoustic distribution result for 125 and 250 Hz is closely matching with experimental results with the maximum of +/-2.7 dB deviation. This shows that simulations agree reasonably well with the measurements in a reverberant chamber. This indicates that FEA can be a good numerical tool to solve vibro-acoustic problems in frequency range upto 250 Hz and lay the foundation to do further study on vibro-acoustics related to shell and plate in aircraft and aerospace applications.
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