PT Unknown AU Hörtnagel, W Zamojsky, M Dohnal, F AU 6. IFToMM D-A-CH Konferenz 2020 : 27./28. Februar 2020, Campus Technik Lienz TI Towards an analytical estimation of the maximum amplitude during passage through resonance at parametric anti-resonance SE Sechste IFToMM D-A-CH Konferenz 2020: 27./28. Februar 2020, Campus Technik Lienz PD 04 PY 2020 VL 2020 DI 10.17185/duepublico/71180 LA de AB During run-up or run-down processes, rotating machines are excited by unbalance forces with continuously increasing or decreasing excitation frequency. If a critical speed has to be passed, the maximum amplitudes during this passage through resonance are a major criterion for the design of the rotor. An analytical prediction of the maximum amplitude is sought in order to allow an efficient design process. We revisit the problem of describing the dynamic response using error functions. Additionally, we apply the homotopy analysis method for deriving an approximation of the maximum vibration amplitude with a time-periodic modulation of the bearing stiffness. ER