This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Energy Finite Element Analysis Methods for Mid-Frequency NVH Applications
Technical Paper
1999-01-1801
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
At low frequencies, the finite element method reliably predicts the dynamic response of structures. At high frequencies where modal density is high, statistical energy analysis (SEA) is a useful tool to determine the global dynamic behavior of the structures. SEA gives only the space frequency band averaged energy for each subsystem. In the mid-frequency range where both short and long waves are present, neither low nor high frequency approximation to the dynamic response is valid. In this frequency range, there is a need to utilize another technique to capture the dynamic response of the structure. In this study, the energy finite element analysis (EFEA) method is evaluated as a possible technique to close the mid-frequency analysis gap related to NVH analyses. EFEA gives spatial variations of energy density and power in each subsystem, and models localized damping treatment and localized power input. In this study, two benchmark problems are used to evaluate both the benefits and limitations of EFEA for the mid-frequency NVH analysis using the commercial EFEA code called Comet-EFEA.1The benchmark problems are the sound transmission loss through a panel, and energy transmission between two beams with different cross-sectional areas. EFEA results for the two problems are compared with the corresponding results obtained by experimentation, conventional finite element analysis, and SEA to establish the applicability and limitations of EFEA for the mid-frequency NVH analysis of automotive components. EFEA provides excellent insight into energy transfer and dissipation through the structure but is limited by the ratio of the geometric dimensions to the wavelengths of interest.
Recommended Content
Technical Paper | Vibroacoustic Optimization of Two Cross Stamped Ribs in a Plate |
Journal Article | A Procedure for Efficient Trimmed Body FE Simulations, Based on a Transfer Admittance Model of the Sound Package |
Technical Paper | NVH CAE Quality Metrics |
Authors
Citation
Gur, Y., Wagner, D., and Morman, K., "Energy Finite Element Analysis Methods for Mid-Frequency NVH Applications," SAE Technical Paper 1999-01-1801, 1999, https://doi.org/10.4271/1999-01-1801.Also In
References
- Bouthier, O.M. Bernhard, R.J. 1992 ‘Models of Space-Averaged Energetics of Plates’ AIAA Journal 30 3 616 623
- Wohlever, J.C. Bernhard, R.J. 1989 ‘Energy Distributions in Rods and Beams’
- Vibro-Acoustic Sciences Limited 1995 ‘Resound Consortium 1995 Technical Review’
- Bremner, P.G. 1987 ‘Finite Element Based Vibro-Acoustics of Panel Systems’ Proceedings of Conference on Finite Element Methods in Engineering Melbourne 19-27 August 1987
- Heron, K.H. 1985 ‘Predicted T.L. of Aluminium Panels Using F.G. Leppington's Damped SEA Formulation’
- Kasper, P. Bremner, P. 1993 “Evaluation of Modal Power Flow (MPF) Approximation Techniques for RESOUND,” Resound Consortium Technical Report, VASci Doc. No. RES-008 rev. 1 Vibro-Acoustic Sciences Ltd.
- Davies, H. G. Wahab, M. A. 1981 “Ensemble Averages of Power Flow in Randomly Excited Coupled Beams,” Journal of Sound and Vibration 71 3 311 321
- Vibro-Acoustic Sciences Limited 1993 “Auto-SEA User Guide.”
- Fahy, F. 1985 Sound and Structural Vibration: Radiation, Transmission and Response London Academic Press, Harcourt Brace Jovanovich
- Blevins, R. D. 1979 Formulas for Frequency and Mode Shape New York van Nostrand Reinhold, Co.