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Efficient, wide-band rigid-body and elastic scattering computations using transient equivalent sources.
1Applied Research Laboratory, The Pennsylvania State University, P.O. Box 30, State College, Pennsylvania 16804, USA.
The Journal of the Acoustical Society of America
|October 9, 2019
Summary
This study extends structural-acoustic analysis to scattering problems using time-stepping methods. The novel approach utilizes a sparse acoustic coupling matrix for efficient, wideband frequency resolution in transient analysis.
Area of Science:
- Computational structural mechanics
- Acoustics
- Numerical analysis
Background:
- Transient structural-acoustic problems are often solved using time-stepping procedures.
- Previous work modeled structures with finite elements and fluids with equivalent sources.
- Scattering problems represent a significant area within structural-acoustic analysis.
Purpose of the Study:
- To extend transient structural-acoustic analysis to include scattering problems.
- To introduce a unique formulation treating the acoustic coupling matrix as sparse.
- To leverage time-domain computations for efficient wideband frequency resolution.
Main Methods:
- Utilizing time stepping procedures for transient analysis.
- Modeling structures with finite elements and fluids with equivalent sources.
- Employing a sparse acoustic coupling matrix for enhanced computational efficiency.
Main Results:
- The analysis successfully incorporates scattering phenomena into transient structural-acoustic models.
- The sparse acoustic coupling matrix formulation demonstrates computational advantages.
- Time-domain computations provide effective wideband frequency resolution, particularly for mid- to high-frequencies.
Conclusions:
- The extended formulation provides an efficient and accurate method for solving transient structural-acoustic scattering problems.
- The use of a sparse acoustic coupling matrix and time-domain computation offers significant benefits over traditional methods.
- The approach is validated through several examples, demonstrating its practical applicability and computational efficiency.
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