Open AccessInstability due to internal damping of rotating shafts
Author(s) -
W Lemahieu,
Mia Loccufier,
Bram Vervisch,
Patrick De Baets
Publication year - 2012
Publication title -
sustainable construction and design
Language(s) - English
Resource type - Journals
eISSN - 2295-9092
pISSN - 2032-7471
DOI - 10.21825/scad.v3i2.20565
Subject(s) - instability , viscous damping , rotor (electric) , physics , beam (structure) , magnetic damping , finite element method , mechanics , structural engineering , classical mechanics , control theory (sociology) , engineering , computer science , vibration , acoustics , quantum mechanics , control (management) , artificial intelligence
Rotor internal damping has been indicated as one of the main causes of instability in rotatingmachinery for more than a century. However, the exact characterisation of this damping is still an unsolvedresearch topic. Therefore, in this thesis the consequences of material damping in rotating shafts areexamined more in depth. Two main steps are considered. Firstly, a finite element model of the beam,including viscous and hysteretic damping, is constructed. This model allows to calculate the thresholdspeed of instability and the resonance frequencies of a shaft. Furthermore it allows to vary the dampingparameters and to compare the considered models giving an indication of the general relations betweeninstability and damping properties. Secondly, an experimental approach should elucidate which model fitsbest for the physical damping. In general, the main purpose is to gain new insights into how the dampingshould really be modelled to have the most accurate and safe prediction of a designed rotor.