Efficiency analysis of vibration based crack diagnostics in rotating shafts

Abstract The vibration based damage detection has practically no alternative as applied to the rotating shafts of steam turbines during operation. A lot of vibration method of damage detection are developed till present time. But the efficiency of all these methods is very dependent on the type of structure, way of its deformation and on the type of damage. At a moment practical engineers have no instrument to make right choice of most appropriate method of damage detection for some or other structure. The comparative estimation of efficiency of different vibration diagnostics methods to detect damage of sub-critical size is complex and time-consuming process. So there was developed quite simple method of selection of most efficient vibration method of damage detection for a certain structure with a certain type of crack and at a certain type of deformation. This method is based on the determination of relative change of shaft’s compliance caused by a crack with the use of linear fracture mechanics. As an example there was performed the comparative sensitivity analysis of several vibration methods of damage detection to the presence of longitudinal and transverse crack in a shaft at bending and torsional vibration.

[1]  A. Sekhar,et al.  Crack detection and vibration characteristics of cracked shafts , 1992 .

[2]  Charles R. Farrar,et al.  Variability of modal parameters measured on the alamosa canyon bridge , 1996 .

[3]  Shahrum Abdullah,et al.  Mode III Stress Intensity Factors of Surface Crack in Round Bars , 2011 .

[4]  A. P. Bovsunovskii,et al.  Fatigue damage and failure of steam turbine rotors by torsional vibrations , 2010 .

[5]  Cecilia Surace,et al.  The effect of damping and force application point on the non-linear dynamic behavior of a cracked beam at sub-and superresonance vibrations , 2006 .

[6]  A. P. Bovsunovskii.  Vibrations of a Nonlinear Mechanical System Simulating a Cracked Body , 2001 .

[7]  Stephen P. Timoshenko,et al.  Vibration problems in engineering , 1928 .

[8]  V. V. Matveev,et al.  VIBRATION-BASED DIAGNOSTICS OF FATIGUE DAMAGE OF BEAM-LIKE STRUCTURES , 2002 .

[9]  Ashish K. Darpe,et al.  Dynamics of a Jeffcott rotor with slant crack , 2007 .

[10]  Andrew D. Dimarogonas,et al.  Stability of Cracked Rotors in the Coupled Vibration Mode , 1988 .

[11]  B. Grabowski,et al.  The Vibrational Behavior of a Turbine Rotor Containing a Transverse Crack , 1980 .

[12]  A. Bovsunovsky.  Energy dissipation in the non-propagating surface cracks in steel round bar at torsional vibration , 2012 .

[13]  Raymond H. Plaut,et al.  Free and Forced Longitudinal Vibrations of a Cantilevered Bar With a Crack , 1992 .

[14]  A. Dimarogonas.  Vibration for engineers , 1992 .

[15]  Anoop Chawla,et al.  Coupled bending, longitudinal and torsional vibrations of a cracked rotor , 2004 .

[16]  S. K. Maiti,et al.  Triply coupled bending-torsion vibration of Timoshenko and Euler-Bernoulli shaft beams with arbitrarily oriented open crack , 2009 .

[17]  Cecilia Surace,et al.  Non-linearities in the vibrations of elastic structures with a closing crack: A state of the art review , 2015 .

[18]  T. Chondros,et al.  Identification of cracks in welded joints of complex structures , 1980 .

[19]  C. Ratcliffe.  DAMAGE DETECTION USING A MODIFIED LAPLACIAN OPERATOR ON MODE SHAPE DATA , 1997 .

[20]  D. J. Ewins,et al.  Management of the variability of vibration response levels in mistuned bladed discs using robust design concepts, Part 1: Parameter design , 2010 .

[21]  T. Chondros,et al.  Analytical Methods in Rotor Dynamics , 1983 .

[22]  Ming Liang,et al.  Experimental investigation of frequency-based multi-damage detection for beams using support vector regression , 2014 .

[23]  A. Barr,et al.  One-dimensional theory of cracked Bernoulli-Euler beams , 1984 .

[24]  Andrew D. Dimarogonas,et al.  Dynamic Sensitivity of Structures to Cracks , 1989 .

[25]  O. S. Salawu.  Detection of structural damage through changes in frequency: a review , 1997 .

[26]  Ming Liang,et al.  A two-step approach to multi-damage detection for plate structures , 2012 .

[27]  H. Petroski.  Simple static and dynamic models for the cracked elastic beam , 1981 .

[28]  M. Yuen.  A NUMERICAL STUDY OF THE EIGENPARAMETERS OF A DAMAGED CANTILEVER , 1985 .

[29]  Andrew D. Dimarogonas,et al.  Coupling of bending and torsional vibration of a cracked Timoshenko shaft , 1987 .

[30]  A. P. Bovsunovskii,et al.  Application of nonlinear resonances for the diagnostics of closing cracks in rodlike elements , 2010 .

[31]  A. K. Darpe,et al.  Coupled vibrations of a rotor with slant crack , 2007 .

[32]  Paolo Pennacchi,et al.  Cracked Rotors: A Survey on Static and Dynamic Behaviour Including Modelling and Diagnosis , 2010 .

[33]  Cecilia Surace,et al.  DAMAGE ASSESSMENT OF MULTIPLE CRACKED BEAMS: NUMERICAL RESULTS AND EXPERIMENTAL VALIDATION , 1997 .

[34]  Thomas G. Chondros,et al.  The continuous crack flexibility model for crack identification , 2001 .

[35]  T. Chondros,et al.  VIBRATION OF A BEAM WITH A BREATHING CRACK , 2001 .