Browse > Article
http://dx.doi.org/10.12989/smm.2019.6.1.033

Vibration modelling and structural modification of combine harvester thresher using operational modal analysis and finite element method  

Zare, Hamed Ghafarzadeh (Department of Mechanical Engineering of Biosystems, Shahrekord University)
Maleki, Ali (Department of Mechanical Engineering of Biosystems, Shahrekord University)
Rahaghi, Mohsen Irani (Department of Mechanical Engineering, University of Kashan)
Lashgari, Majid (Department of Mechanical Engineering of Biosystems, Arak University)
Publication Information
Structural Monitoring and Maintenance / v.6, no.1, 2019 , pp. 33-46 More about this Journal
Abstract
In present study, Operational Modal Analysis (OMA) was employed to carry out the dynamic and vibration analysis of the threshing unit of the combine harvester thresher as a mechanical component. The main study is to find the causes of vibration and to decrease it to enhance the lifetime and efficiency of the threshing unit. By utilizing OMA, structural modal parameters such as mode shapes, natural frequencies, and damping ratio was calculated. The combine harvester was excited by engine to vibrate different parts and accelerometer sensor collected acceleration signals at different speeds, and OMA was utilized by nonparametric and frequency analysis methods to obtain modal parameters while vibrating in real working conditions. Afterwards, finite element model was designed from the thresher and updated using the data obtained from the modal analysis. Using the conducted analyses, it was specified that proximity of the thresher pass frequency to one of the natural frequencies (16.64 Hz) was the most important effect of vibration in the thresher. Modification process of the structure was carried out by increasing mass required for changing the natural frequency location of the first mode to 12.4 Hz in order to reduce resonance and vibration of the thresher.
Keywords
structural modification; operational modal analysis; vibrations; thresher;
Citations & Related Records
연도 인용수 순위
  • Reference
1 Brincker, R., Zhang, L. and Andersen, P. (2001), "Modal identification of output only systems using frequency domain decomposition", Smart Mater. Struct., 10, 441- 445.   DOI
2 Cara, J. (2016), "Computing the modal mass from the state space model in combined experimental - operational modal analysis", J. Sound Vib., 370, 94-110.   DOI
3 Chandravanshi, M.L. and Mukhopadhyay, A.K. (2017), "Analysis of variations in vibration behavior of vibratory feeder due to change in stiffness of helical springs using FEM and EMA methods", J. Braz. Soc. Mech. Sci. Eng., 39, 3343-3362.   DOI
4 Christof, D., Gert, D. and Patrick, G. (2010), "An operational modal analysis approach based on parametrically identified multivariable transmissibilities", Mech. Syst. Signal Pr., 24, 1250-1259.   DOI
5 Deoliveira, F.M.V.M., Ipina, J.E.P. and Bavastri C.A. (2018), "Experimental identification of structural changes and cracks in beams using a single accelerometer", J. Braz. Soc. Mech. Sci. Eng., 40(106).
6 Donoho, D.L. (1995), "De-noising by Soft-thresholding", IEEE T. Inform. Theory, 613-627.
7 Ewins, D.J. (2000), Modal Testing: Theory Practice and Application, Research Studies Press Ltd. England.
8 Hanson, D. (2006), Operational Modal Analysis and Model Updating with a Cyclostationary Input, PhD Thesis, University of New South Wales, Australia.
9 Ibrahim, S.R. and Mikulcik, E.C. (1997), "A method for the direct identification of vibration parameters from the free response", Shock Vib. Bulletin, 47, 183-198.
10 Khatibi, M.M., Ashory, M.R., Malekjafarian, A. and Brincker, R. (2012), "Mass-stiffness change method for scaling of operational mode shapes", Mech. Syst. Signal Pr., 26, 34-59.   DOI
11 Zhang, L., Brincker, R. and Andersen, R. (2005), "An overview of operational modal analysis major development and issues", Proceedings of the 1st International Operational Modal Analysis Conference (IOMAC), Copenhagen Denmark, 262-269.
12 Ziaeirad, S. (1997), Methods for Updating Numerical Models in Structural Dynamic, PhD Thesis, Imperial College London.
13 Bing, B., Zhang, L., Guo, T. and Liu, C. (2012), "Analysis of dynamic characteristics of the main shaft system in a hydro-turbine based on ansys", J. Procedia Eng., 31, 654-658.   DOI
14 Brandt, A. (2011), Noise and Vibration Analysis: Signal Analysis and Experimental Procedures. 1st Ed., John Wiley & Sons.
15 Brewick, P. and Smyth, A. (2013), "An investigation of the effects of traffic induced local dynamics on global damping estimates using operational modal analysis", Mech. Syst. Signal Pr., 41, 433-453.   DOI
16 Magalhaes, F., Caetano, E. and Cunha, A. (2008), "Operational modal analysis and finite element model correlation of the Braga Stadium suspended roof", Eng. Struct., 30, 1688-1698.   DOI
17 Kyprianou, A., Mottershead, J.E. and Ouyang, H. (2005), "Structural modification. Part 2: assignment of natural frequencies and antiresonances by an added beam", J. Sound Vib., 284, 267-281.   DOI
18 Li, X. and Chen, L.T. (2008), "Modal analysis of coupled vibration of belt drive systems", Appl. Math. Mech. - Engl., 29, 9-13.   DOI
19 Lim, H., Chung, J. and Yoo, H. (2009), "Modal analysis of a rotating multi-packet blade system", J. Sound Vib., 325, 513-531.   DOI
20 Misiti, M., Misiti, Y., Oppenheim, G. and Poggi, J. (2008), Matlab user's guide: wavelet $toolbox^{TM}$ 4. Natick (Mass): The Math Works Inc.
21 Miu, P.I. (2004), "Mathematical modeling of material other than grain separation in threshing units", ASAE Meeting Presentation, ASAE Paper No. 993208. ASAE, St. Joseph, MI, USA.
22 Mohanty, P. and Rixen, D.J. (2004), "A modified Ibrahim time domain algorithm for operational modal analysis including harmonic excitation", J. Sound Vib., 275, 375-390.   DOI
23 Moosavian, A., Khazaee, M., Najafi, G.H., Kettner, M. and Mamat, R. (2015), "Spark plug fault recognition based on sensor fusion and classifier combination using Dempster-Shafer evidence theory", Appl. Acoust., 93, 120-129.   DOI
24 Park, Y.H. and Park, Y.S. (2000), "Structural modification based on measured frequency response function: an exact eigenproperties reallocation", J. Sound Vib., 237, 411-426.   DOI
25 Wenzel, H. and Pichler, D. (2005), Ambient Vibration Monitoring. 1st Ed., John Wiley & Sons.
26 Rahmatalla, S., Hudson, K. and Liu, Y. (2013), "Finite element modal analysis and vibration-waveforms in health inspection of old bridges", J. Finite Elem. Anal. Des., 78, 40-46.   DOI
27 Rovscek D., Slavic J. and Boltezar M. (2014), "Operational mode-shape normalisation with a structural modification for small and light structures", Mech. Syst. Signal Pr., 42, 1-13   DOI
28 Tarinejad, R. and Damadipour, M. (2014), "Modal identification of structures by a novel approach based on FDD-wavelet method", J. Sound Vib., 333, 1024-1045.   DOI
29 Zhang, G., Ma, J., Chen, Z. and Wang, R. (2014), "Automated eigensystem realization algorithm for operational modal analysis", J. Sound Vib., 333, 3550-3563.   DOI