Browse > Article
http://dx.doi.org/10.5762/KAIS.2019.20.4.489

An Evaluation of Loss Factor of Damping Treatment Materials for Panels of Railway Vehicles  

Kang, Gil-Hyun (Technical Division, SR Corp.)
Publication Information
Journal of the Korea Academia-Industrial cooperation Society / v.20, no.4, 2019 , pp. 489-496 More about this Journal
Abstract
This paper is a study on the evaluation of loss factor of damping treatment materials to reduce the noise and vibration for panels of railway vehicles and automobiles. In order to determine the modal parameters of damping materials, beam excitation tests were carried out using different type PVC coated aluminum and steel base beam specimens. The specimens were excited from 10 Hz to 1000 Hz frequency range using sinusoidal force, and transfer mobility data were measured by using an accelerometer. The loss factors were determined by using integrated program, based on theories of Half Power Method, Minimum Tangent Error Method, Minimum Angle Error Method and Phase Change Method, which enable to evaluate the parameters using modal circle fit and least squares error method. In the case of lower loss factor and data of linear characteristics, any method could be applied for evaluation of parameters, however the case of higher loss factor or data including non-linear characteristics, the minimum angle error method could reduce the loss factor evaluation. The obtained dynamic properties of the coating material could be used for application of Finite Element Method analyzing the noise control effects of complex structures such as carbody or under-floor boxes of rolling stock. The damping material will be very useful to control the structural noise, because the obtained modal loss factors of each mode show very good effect on over $2^{nd}$ mode frequency range.
Keywords
Beam Tests; Loss Factor; Dynamic Characteristics; Half Power Method; Minimum Tangent Error Method; Minimum Angle Error Method; Phase Change Method;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
1 D. J. Ewins and J. Griffin, "A State-of-the-art Assessment of Mobility Measurement Techniques-Results for the mid-range Structure (30-3000Hz)", Journal of Sound and Vibration, Vol. 78, No. 2, pp.197-222, 1981. DOI: https://doi.org/10.1016/S0022-460X(81)80033-8   DOI
2 Gil-Hyun Kang and Chul-Su Kim, "Damping Characterization of the Double-skin Aluminum Extruded Panels for rolling Stock Carbody", Journal of the Korea Academia-Industrial cooperation Society, Vol. 14. No. 7, pp.3198-3199, July 2013. DOI: http://dx.doi.org/10.5762/KAIS.2013.14.7.3197
3 C. C. Kennedy and C. D. P. Pancu, "Use of Vectors in Vibration Measurement and Analysis", Journal of Aero Science, Vol. 14, No. 11, pp.603-625, 1947. DOI: https://doi.org/10.2514/8.1474   DOI
4 A. M. Brown, An Experimental and Theoretical Analysis of Vehicle Body Structure Dynamics, Ph.D. Thesis, The University of Birmingham, Birmingham, UK, pp.60-74, 1985.
5 D. L. Brown, R. J. Allemang, R. Zimmerman, and M. Mergeay, "Parameter Estimation Techniques for Modal Analysis", SAE Transactions, paper No. 790221, pp.828-846, 1979. DOI: https://doi.org/10.4271/790221
6 D. J. Mead, The Internal Damping Due to Structural Joint and Techniques for General Damping Measurements, C.P. No. 452, A.R.C. Technical Report, p.14, Her Majesty's Office, 1959. Available from: http://naca.central.cranfield.ac.uk/reports/arc/cp/0452.pdf (accessed Dec. 10, 2018)
7 H. Oberst unter Mitwirkung von K. Frankenfeld, "Uber die Dampfung der Bigeschwingungen dunner Bleche durch fest haftendende Belage", Acustica, Akustische Beiheft 4, Vol. 2, pp.AB181-AB194, 1952.
8 H. Oberst, "Reduction of Noise by the Use of Damping Materials", Philosophical Transactions of the Royal Society of London, Series A, Vol. 263, No. 1142, pp.441-453, 1968. Available from: https://www.jstor.org/stable/73401   DOI
9 ASTM E756-05, Standard method for Measuring Vibration-damping Properties of Materials, American Society for Testing and Materials, ASTM, 2017. DOI: https://doi.org/10.1520/E0756-05R17