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The surface variational principle applied to an acoustic cavity
1Dipartimento di Progettazione Aeronautica, Università di Napoli Federico II, Italy. francof@unina.it
The Journal of the Acoustical Society of America
|June 27, 2001
Summary
This study introduces the Surface Variational Principle (SVP) for interior acoustics, accurately predicting acoustic responses in axisymmetric domains. The method shows excellent agreement with analytical solutions for elastic cylinders.
Area of Science:
- Acoustics
- Computational Mechanics
- Applied Mathematics
Background:
- The Surface Variational Principle (SVP) is an established method for exterior acoustics.
- Evaluating interior acoustic domains requires specialized formulations.
Purpose of the Study:
- To develop and apply the interior form of the Surface Variational Principle (SVP).
- To analyze the interior acoustic response of axisymmetric domains.
Main Methods:
- Developed the interior SVP formulation.
- Utilized Ritz expansion for surface pressure and normal velocity.
- Applied the method to a harmonically forced, right circular elastic cylinder.
Main Results:
- The SVP accurately reproduced analytical solutions for validation models.
- Demonstrated asymptotic convergence characteristic of variational methods.
- Validated results for length-to-radius ratios of 2.4 and 12.3.
Conclusions:
- The developed interior SVP is effective for analyzing axisymmetric interior acoustic problems.
- The formulation is adaptable to various axisymmetric geometries beyond cylinders.
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