Recent Developments in Turbomachinery Modelling for Improved Balancing and Vibration Response Analysis Available to Purchase

Present day turbogenerator installations are statically indeterminate rotor-bearing-foundation systems utilising non-linear hydrodynamic bearings. For optimal balancing and diagnostic purposes it is important to be able to correctly predict the system vibration behaviour over the operating speed range. Essential aspects of this involve identifying the unbalance state, identifying appropriate dynamic foundation parameters, and identifying the system configuration state (relative location of the support bearings). This paper shows that provided the system response is periodic at some speeds over the operating range, and provided appropriate rotor and bearing housing motion measurements are made, it is possible in principle to satisfactorily achieve the above identifications without relying on Reynolds equation for evaluating bearing forces; and preliminary results indicate that the identifications achieved promise to be superior to identification approaches which use Reynolds equation.