Experimental vibroacoustic testing of plane panels using synthesized random pressure fields

Area of Science:

• Acoustics
• Vibroacoustics
• Structural Dynamics

Background:

• Reproducing random pressure fields for vibroacoustic analysis is challenging.
• Existing methods may lack accuracy or efficiency in simulating complex acoustic environments.
• Understanding panel response to diffuse acoustic fields and turbulent boundary layers is crucial for structural integrity.

Purpose of the Study:

• To experimentally reproduce random pressure fields on a plane panel.
• To investigate the induced vibrations and vibroacoustic behavior of the panel.
• To validate a novel open-loop reproduction strategy using the synthetic array concept.

Main Methods:

• An open-loop reproduction strategy employing the synthetic array concept was developed.
• Three approaches for defining source complex amplitudes were proposed.
• Experiments utilized a single acoustic monopole, scanning laser vibrometer, and a baffled aluminum panel.
• Vibroacoustic indicators like Transmission Loss were measured under diffuse acoustic and turbulent boundary layer excitations.

Main Results:

• The experimental reproduction of random pressure fields and induced panel vibrations was achieved.
• Transmission Loss estimations were successfully obtained for both diffuse acoustic field and turbulent boundary layer excitations.
• Comparisons with commercial software simulations showed good agreement for Transmission Loss.
• The study confirmed the feasibility of analyzing vibroacoustic behavior in the wave number domain.

Conclusions:

• The proposed synthetic array concept provides an effective method for reproducing random pressure fields.
• Accurate Transmission Loss estimation is achievable under challenging acoustic excitations.
• The wave number domain offers valuable insights into panel vibroacoustic behavior complementing frequency domain analysis.