...-mail:  patrick.b.lamas@usp.br e-mail:  rnicolet@sc.usp.br 04 04 2022 29 08 2022 29 11 2022 rotordynamics vibration structural dynamics modal analysis Fig. 4 Experimental frequency bandwidth of the band gap 1 in comparison to the average modal spacing of the system up to 400 Hz...

... to evaluate these matrices at ω 0 , then use the new natural frequency ω to recalculate the matrices C and D and repeat this procedure until a converged value ω is obtained. This iterative method is principally used to solve modal analysis of structures with frequency-dependent, nonproportional...

... of the different sectors, which can be obtained from a usual cyclic symmetry modal analysis. Hence the projection basis is constituted; as well as, on the whole bladed disk, each sector matrix is reduced by its own modes. The method is validated numerically on a real bladed disk model, by comparing free and forced...

... is established in which the contact stress is defined by the pretightening force. The relationship is then applied on the modal analysis of a real gas turbine rotor, and its modal test results and finite element analysis results are consistent with each other, proving that the relationship and the described...

... to vibrate at resonance. In order to illustrate the modal shapes of the main blade during resonant vibration, two studies were conducted. First of all, a modal analysis calculation was performed using finite element model (FEM) and a cyclically symmetrical model. Second, the modal shapes were optically...

... 11 08 2004 rotors modal analysis parameter estimation calibration vibration measurement Balancing of flexible rotors has acquired the attention of many researchers since the days of Thearle 1 . The main balancing techniques are the influence coefficient method, 2...

... element modal analysis at three different rotational speeds. Once the model is determined then the frequencies of the two modes and the modal content can be quickly calculated over a wide range of speeds. The expression for the modal content can be used to give the modal stresses in the blade...

.... 01 Nov 2000 01 May 2002 27 12 2002 vibrations modal analysis parameter estimation gas turbines rotors bending numerical analysis The evaluation of the vibration behavior of gas turbine installations where the rotor support structure or casing has natural frequencies...

... periodic system of elements vibrational modes modal analysis harmonics sensitivity stability modelling Turbine engine bladed disks belong to a class of structures generally referred to as periodic. Such structures exhibit families of extended modes with closely spaced natural frequencies...

... Division, October 2000; final revision, August 2001. Associate Editor: M. Mignolet. 01 10 2000 01 08 2001 26 03 2002 rotors gas turbines compressors dynamics random processes modelling modal analysis stress analysis finite element analysis statistical...

... to the retained component interface degrees of freedom. It is demonstrated that this problem is alleviated by a secondary modal analysis reduction technique (SMART). In addition, a non-CMS mistuning projection method is considered. Although this method is elegant and accurate, it is seen that it lacks...

...R. Bladh, Graduate Student; M. P. Castanier, Assistant Research Scientist; C. Pierre, Professor Component mode synthesis (CMS) techniques are widely used for dynamic analyses of complex structures. Significant computational savings can be achieved by using CMS, since a modal analysis is performed...

... received by the ASME Headquarters June 9, 1999. Editor: H. D. Nelson. 04 May 1999 09 June 1999 rotors turbines vibrations vibrational modes modal analysis identification parameter estimation frequency response elasticity mass In regards to the maximum likelihood (ML...

... vibrations vibrational modes modal analysis identification parameter estimation frequency response elasticity mass A large number of investigations have focused, in the last thirty years, on the assessment of the effects of mistuning, i.e., small blade-to-blade variations of their mechanical...