Modal decomposition of exterior acoustic-structure interaction problems with model order reduction

Area of Science:

• Computational mechanics
• Acoustics
• Structural dynamics

Background:

• Analyzing acoustic responses of submerged structures is computationally intensive.
• Fully coupled finite element/boundary element models are often required for accurate simulation.
• Reducing computational effort is crucial for practical applications in acoustic-structure interaction.

Purpose of the Study:

• To present a numerical technique for modal decomposition of acoustic responses of structures in heavy fluids.
• To introduce a Krylov subspace model order reduction approach for efficient analysis.
• To provide greater physical insight into exterior acoustic-structure interaction problems.

Main Methods:

• A Krylov subspace model order reduction is applied to the structural part of a fully coupled finite element/boundary element model.
• Frequency-independent finite element matrices are reduced.
• The technique is demonstrated on a fluid-loaded cylindrical shell with hemispherical end caps.

Main Results:

• The method significantly reduces computational effort for fully coupled acoustic-structure interaction problems.
• Individual contributions of cylinder circumferential modes to sound power and directivity are observed.
• The technique allows for detailed analysis of acoustic radiation from submerged structures.

Conclusions:

• The presented numerical technique offers an efficient approach for modal decomposition of acoustic responses.
• The Krylov subspace reduction method enhances physical insight into complex acoustic-structure interaction.
• This tool is valuable for analyzing submerged structures with reduced computational demands.