Influence of Damping on the Bending and Twisting Modes of Flax Fibre-reinforced Polypropylene Composite

다국어 초록 (Multilingual Abstract)

The effects of damping on the bending and twisting modes of flax fibre-reinforced polypropylene composites are investigated. The laminate was manufactured by a vacuum bagging process; its dynamic behaviour was then found from the vibration measurements of a beam test specimen using an impulse hammer technique to frequencies of 1 kHz. The frequency response of a sample was measured, and the bending and twisting responses at resonance were used to estimatethe natural frequency and loss factor. The single-degree-of-freedom circle-fit method and Newton’s divided differences formula were used to estimate the natural frequencies as well as the loss factors. The damping estimates were also investigated using a “carpet” plot. The results show significant variations in loss factors depending on the type of mode. The loss factor generally lies in the range of 1.7-2.2 % for the bending modes, while 4.8 % on average for the twisting modes. Numerical estimates of the response, and in particular the natural frequencies, were made using a Mechanical APDL (ANSYS parametric design language) finite element model, with the beam being discretised into a number of shell elements. The natural frequencies from the finite element analysis show reasonably good agreement (errors < 5 %) with the measured natural frequencies.

참고문헌 (Reference)

1 F. Duc, 102 : 94-, 2014

2 S. M. Panamoottil, The University of Auckland 2015

3 D. D. L. Chung, 36 : 5733-, 2001

4 F. Duc, 64 : 115-, 2014

5 R. Adams, 355 : 126-, 2003

6 R. Chandra, 262 : 475-, 2003

7 Y. Gao, 19 : 119-, 2011

8 M. Z. Rahman, 18 : 2187-, 2017

9 E. Barbero, 32 : 1859-, 1995

10 R. Luciano, 31 : 2933-, 1994

11 R. Luciano, 62 : 786-, 1995

12 J. Silva, 124 : 13-, 1988

13 R. F. Gibson, 92 : 2793-, 2010

14 L. D. Landro, 3 : 238-, 2009

15 L. D. Landro, 286 : 145-, 2009

16 K. S. Kumar, 56 : 379-, 2014

17 M. Assarar, 132 : 148-, 2015

18 K. Cheour, 152 : 259-, 2016

19 A. Etaati, 33 : 330-, 2013

20 J.-M. Berthelot, 74 : 186-, 2006

21 J.-M. Berthelot, 85 : 189-, 2008

22 S. Hwang, 28 : 1-, 1993

23 Y. Hong, 19 : 81-, 2011

24 M. Z. Rahman, 2017

25 S. Kazmi, 214 : 2375-, 2014

26 N. Maia, "Theoretical and Experimental Modal Analysis" Research Studies Press Ltd 219-227, 1997

27 D. J. Ewins, "Modal Testing: Theory, Practice and Application" Research Studies Press Ltd 310-318, 2000

28 M. H. Datoo, "Mechanics of Fibrous Composites" Springer 2012

29 R. M. Jones, "Mechanics of Composite Materials" CRC Press 1998

30 "MATLAB R2013b" 2013

31 E. J. Barbero, "Introduction to Composite Materials Design" CRC Press 2010

32 D. I. Jones, "Handbook of Viscoelastic Vibration Damping" John Wiley & Sons Ltd. 7-, 2001

33 E. J. Barbero, "Finite Element Analysis of Composite Materials Using $ANSYS^{(R)}$" CRC Press 2013

34 "ANSYS R16.0."