Model-Based Fault Diagnosis Approach for Rotor System with Unidentified Supporting Parameters

Abstract:

The model based diagnosis method can detect both the fault location and the fault extent of the rotating machinery at the same time as it can combine the dynamics and fault diagnosis method together. However, the modal test of the supporting part is necessary when using the existing model based method, and the precision of the modal test results make a strong impact on the diagnosis results. In order to improve this case, an improved model based diagnosis method is presented herein by combining the fixed-interface modal synthesis method with the traditional model based diagnosis method. The DOF of the unidentified parameter due to the supporting parts are partitioned to interface DOF, and the displacement information of the supporting parts can be measured by the mounted sensors. Therefore, the model based diagnosis method can be carried out by only using the parameters of the rotor without considering the effects from the supporting, which can greatly improve the diagnosis precision and efficiency. This method is fit for the rotor systems with unidentified supporting parameter, and the rotor systems with unknown nonlinear supporting parameter. Both the numerical simulation results and the experiment results in the example proved the efficiency of this method.

• Periodical: Advanced Engineering Forum (Volumes 2-3)
• Pages: 773-778
• DOI: https://doi.org/10.4028/www.scientific.net/AEF.2-3.773
• Online since: December 2011
• Authors: Hong Liang Yao, Hong Bin Ma, Qing Kai Han, Bang Chun Wen
• Keywords: Fixed-Interface Modal Synthesis Method, Model Based Diagnosis Method, Rotating Machinery

References

[1] Wen, B., et al., The nonlinear dynamic theory and experiment of the fault rotating machinery. Beijing, Science Press (2004) (In chinese).

[2] Markert, R., Platz, R., Seidler, M., Model based fault identification in rotor systems by least square fitting. Proceedings of the 8th international symposium on transport phenomena and dynamics of rotating machinery, ISROMAC-8, Vol. II, 900-906 (2000).

DOI: 10.1155/s1023621x01000264

[3] Sekhar, A. S., Crack identification in a rotor system, a model-based approach. Journal of Sound and Vibration. 270 (2004) 887-902.

DOI: 10.1016/s0022-460x(03)00637-0

[4] Sekhar, A. S., Model-based identification of two cracks in a rotor system. Mechanical Systems and Signal Processing. 18 (2004) 977–983.

DOI: 10.1016/s0888-3270(03)00041-4

[5] Jain, J. R., Kundra, T. K., Model based online diagnosis of unbalance and transverse fatigue crack in rotor systems. Mechanics Research Communications. 31 (2004) 557–568.

DOI: 10.1016/j.mechrescom.2003.11.002

[6] Jalan, A. K., Mohanty, A. R., Model based fault diagnosis of a rotor–bearing system for misalignment and unbalance under steady-state condition. Journal of Sound and Vibration. 327 (2009) 604–622.

DOI: 10.1016/j.jsv.2009.07.014

[7] Yao, H. L., Li, H., Li, X. P., Wen, B. C., Diagnosis of local fault and identification of transient fault force in rotating machinery. Journal of Mechanical Engineering, 43 (2007) 120-124 (In chinese).

DOI: 10.3901/jme.2007.01.120

[8] Bachschmid, N., Pennacchi, P., Vania, A., Identification of multiple faults in rotor systems. Journal of Sound and Vibration, 254 (2002) 327-366.

DOI: 10.1006/jsvi.2001.4116

[9] Pennacchi, P., Bachschmid, N., Vania, A., A model-based identification method of transverse cracks in rotating shafts suitable for industrial machines. Mechanical Systems and Signal Processing 20 (2006) 2112–2147.

DOI: 10.1016/j.ymssp.2005.04.005

[10] Pennacchi, P., Vania, A., Accuracy in the identification of a generator thermal bow. Journal of Sound and Vibration 274 (2004) 273–295.

DOI: 10.1016/j.jsv.2003.05.014

[11] Han, Q. K., Yao, H. L., Wen, B. C., Parameter identification for a rotor system based on its finite element model and with varying speeds. Acta Mech Sin 26 (2010) 299-303.

DOI: 10.1007/s10409-009-0324-9

[12] Sinha, J. K., Lees, A .W., Friswell, M. I., Estimating unbalance and misalignment of a flexible rotating machine from a single run-down. Journal of Sound and Vibration. 272 (2004) 967–989.

DOI: 10.1016/j.jsv.2003.03.006

[13] Edwards, S., Lees, A .W., Friswell, M. I., Experimental identification of excitation and support parameters of a flexible rotor-bearings-foundation system from a single run-down. Journal of Sound and Vibration. 232(2000), 63-992.

DOI: 10.1006/jsvi.1999.2779

[14] Lees, A. W., Sinha, J. K., Friswell, M. I., Model-based identification of rotating machines. Mechanical Systems and Signal Processing. 23 (2009) 1884–1893.

DOI: 10.1016/j.ymssp.2008.08.008