doi: 10.52899/24141437_2026_01_63
UDK: 621.82:004.94, 534.1:62-1/-9

Effect of Support Rigidity on Modal Parameters of Multi-Supported Rotors

Изотов Н. В., Портнова О. С., Плаксин Р. А., Васютина А. А., Нестеренко И. А.
Article language:
Citation Link: Izotov NV, Portnova OS, Plaksin RA, Vasyutina AA, Nesterenko IA. Effect of Support Rigidity on Modal Parameters of Multi-Supported Rotors. Transactions of the Saint Petersburg State Marine Technical University. 2026;5(1):63–68. DOI: 10.52899/24141437_2026_01_63 EDN: WSMXZF

Annotation

BACKGROUND: The study on the effect of support rigidity on modal parameters of multi-supported rotors is relevant as scientific and technical publications mainly analyze data for two-support rotor systems. The findings should be considered when balancing multi-supported rotor systems on their supports. AIM: To study the effect of variable support rigidity on the modal parameters of a multi-supported rotor; to determine the relationship between the natural vibration frequency and the ratio of the support and rotor rigidity, and to identify relationships between changes in the natural vibration mode shapes and the support rigidity. METHODS: The study used the Fidesys software suite. The method involved creating a digital model of a four-support rotor, followed by changing their rigidity in the range of 10⁻⁶–10⁸ N/mm. The rotor modal parameters were investigated at each rigidity value. RESULTS: It is shown that the higher the rigidity of the supports, the higher the natural vibration frequency of the rotor following a nonlinear law. The study identified the following patterns: at Kc >105, the modal parameters are identical to the values obtained for a structure with absolutely rigid supports; in the range of Kc from 10-6 to 105 , a nonlinear frequency change occurs; at Kc Keywords: rotor; rigidity; modal analysis; natural frequencies; natural mode shape.

Bibliography

1. Nikhamkin MA. Vibrational processes in gas turbine engines. Perm’: Izd-vo Permskogo nats. issled. politekhnicheskogo un-ta, 2011. 117 p. (In Russ.) EDN: QNYFVP
2. Izotov NV, Portnova OS, Vasyutina AA, Nesterenko IA. Analysis of existing research in the field of digital technologies and modal analysis of rotor systems. New strategies and technologies for maritime navigation and fishing: рroceedings of the National Scientific and Technical Conference at the Kaliningrad State Technical University, Kaliningrad, March 27, 2025. Kaliningrad: Izdatel’stvo BGARF, 2025. P. 4-7. (In Russ.) EDN: XQCWJZ
3. Uriev EV, Shaposhnikov KV. Balancing of rotors with long overhangs at the high-speed balancing facilities. Russian journal of heavy machinery. 2011;7:14-21. (In Russ.) EDN: OJSYKJ
4. Bently DE. Fundamentals of Rotating Machinery Diagnostics. USA: Bently Press, 2002. 764 p.
5. Kleimanov RV, Korshunov AV. Rotor displacement analysis of turbomachines with fea using. Compressors and pneumatics. 2016;2:45. (In Russ.) EDN: VTKILF
6. Frolov AV, Savvateev DO, Shapovalov PA. Modal analysis of the model sins using Ansys. Izvestiya TulGU. Technical sciences. 2022;11:36-53. (In Russ.) doi: 10.24412/2071-6168-2022-11-36-53 EDN: QLMIAA
7. Lipin AA, Vakhidov USh, Vishnyakov AV, Strizhak AD. Research of natural frequencies of fluctuations of screw-propelled propulsion. Vestnik IzhGTU imeni M.T. Kalashnikova. 2017;4:3-6. (In Russ.) doi: 10.22213/2413-1172-2017-4-3-6 EDN: ZVEWOX