A finite element-based algorithm for rubbing induced vibration prediction in rotors

Abstract In this paper, an algorithm is developed for more realistic investigation of rotor-to-stator rubbing vibration, based on finite element theory with unilateral contact and friction conditions. To model the rotor, cross sections are assumed to be radially rigid. A finite element discretization based on traditional beam theories which sufficiently accounts for axial and transversal flexibility of the rotor is used. A general finite element discretization model considering inertial and viscoelastic characteristics of the stator is used for modeling the stator. Therefore, for contact analysis, only the boundary of the stator is discretized. The contact problem is defined as the contact between the circular rigid cross section of the rotor and “nodes” of the stator only. Next, Gap function and contact conditions are described for the contact problem. Two finite element models of the rotor and the stator are coupled via the Lagrange multipliers method in order to obtain the constrained equation of motion. A case study of the partial rubbing is simulated using the algorithm. The synchronous and subsynchronous responses of the partial rubbing are obtained for different rotational speeds. In addition, a sensitivity analysis is carried out with respect to the initial clearance, the stator stiffness, the damping parameter, and the coefficient of friction. There is a good agreement between the result of this research and the experimental result in the literature.

[1]  Matthew P. Cartmell,et al.  Regular and chaotic dynamics of a discontinuously nonlinear rotor system , 2002 .

[2]  F. F. Ehrich,et al.  Observations of Subcritical Superharmonic and Chaotic Response in Rotordynamics , 1992 .

[3]  O. C. Zienkiewicz,et al.  The Finite Element Method for Solid and Structural Mechanics , 2013 .

[4]  Guanrong Chen,et al.  Nonlinear responses of a rub-impact overhung rotor , 2004 .

[5]  Donald E. Bently,et al.  Rotor/Seal Experimental and Analytical Study on Full Annular Rub , 2002 .

[6]  Peter W. Tse,et al.  Detection of the rubbing-caused impacts for rotor–stator fault diagnosis using reassigned scalogram , 2005 .

[7]  D. Ewins,et al.  The Harmonic Balance Method with arc-length continuation in rotor/stator contact problems , 2001 .

[8]  J. Padovan,et al.  Non-linear transient analysis of rotor-casing rub events , 1987 .

[9]  K. Bathe Finite Element Procedures , 1995 .

[10]  R. Taylor,et al.  Lagrange constraints for transient finite element surface contact , 1991 .

[11]  Paolo Pennacchi,et al.  Light and short arc rubs in rotating machines: Experimental tests and modelling , 2009 .

[12]  Z. C. Feng,et al.  Rubbing phenomena in rotor–stator contact , 2002 .

[13]  M. Wiercigroch,et al.  Non-linear dynamic interactions of a Jeffcott rotor with preloaded snubber ring , 2004 .

[14]  B. O. Al-Bedoor TRANSIENT TORSIONAL AND LATERAL VIBRATIONS OF UNBALANCED ROTORS WITH ROTOR-TO-STATOR RUBBING , 2000 .

[15]  Peter Wriggers,et al.  Computational Contact Mechanics , 2002 .

[16]  D. Childs Rub-Induced Parametric Excitation in Rotors , 1979 .

[17]  Fulei Chu,et al.  Stiffening effect of the rotor during the rotor-to-stator rub in a rotating machine , 2007 .

[18]  Christophe Pierre,et al.  Modeling of a rotor speed transient response with radial rubbing , 2010 .

[19]  Michel Lalanne,et al.  Rotordynamics prediction in engineering , 1998 .

[20]  Guang Meng,et al.  Stability, bifurcation and chaos of a high-speed rub-impact rotor system in MEMS , 2006 .

[21]  Xingjian Dai,et al.  The partial and full rubbing of a flywheel rotor–bearing–stop system , 2001 .

[22]  Alexander Robert Bartha Dry friction backward whirl of rotors , 2000 .

[23]  Fulei Chu,et al.  DETERMINATION OF THE RUBBING LOCATION IN A MULTI-DISK ROTOR SYSTEM BY MEANS OF DYNAMIC STIFFNESS IDENTIFICATION , 2001 .

[24]  Yeon Sun Choi On the contact of partial rotor rub with experimental observations , 2001 .