Journal of Mechanical Science and Technology

, Volume 29, Issue 7, pp 2735–2746 | Cite as

Complex harmonic modal analysis of rotor systems

  • Dong Ju HanEmail author


Complex harmonic analysis for rotor systems has been proposed from the strict complex modal analysis based upon Floquet theory. In this process the harmonic balance method is adopted, effectively associated with conventional eigenvalue analysis. Also, the harmonic coefficients equivalent to dFRFs in harmonic mode has been derived in practice. The modes are classified from identifying the modal characteristics, and the adaptation of harmonic balance method has been proven by comparing the results of the stability analyses from Floque theory and the eigen analysis. The modal features of each critical speed are depicted in quantitatively and qualitatively by showing that the strengths of each component of the harmonic coefficients are estimated from the order of magnitude analysis according to their harmonic patterns. This effectiveness has been verified by comparing with the numerical solutions.


Critical speed Directional frequency responses Floquet theory Harmonic modal analysis Rotor systems Stability 


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Copyright information

© The Korean Society of Mechanical Engineers and Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  1. 1.Department of Aerospace Maintenance EngineeringFar East UniversityChungbukKorea

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