Vibration Characteristics of a Dual-Rotor System with Non-Concentricity

Autor: Shengliang Hou, Lei Hou, Shiwei Dun, Yufeng Cai, Yang Yang, Yushu Chen
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Machines, Vol 9, Iss 11, p 251 (2021)
Druh dokumentu: article
ISSN: 2075-1702
DOI: 10.3390/machines9110251
Popis: A finite element model of an aero-engine dual-rotor system with intermediate bearing supported by six bearings is set up. Three modes of non-concentricity caused by the assembly process are defined, namely parallel non-concentricity, front deflection angle non-concentricity and rear deflection angle non-concentricity. The influence of the non-concentricity on the vibration characteristics of the dual-rotor system is investigated in detail. The results show that the parallel non-concentricity and the front deflection angle non-concentricity have a significant influence on the bending vibration modals of the high-pressure rotor and the low-pressure rotor, but have little influence on the local vibration modals of the rotors. With the increase in the magnitude of the non-concentricity, the natural frequencies of the bending modals decrease continuously, and the mode shapes of bending modals and that of local modals may be interchanged, leading to the emergence of bending modals in advance. Therefore, the key parameters to be controlled in the assembly process are the parallel non-concentricity and the front deflection angle non-concentricity. In order to prevent the bending modal of the dual-rotor system from appearing in advance, it is necessary to control the parallel non-concentricity within 2 mm and the front deflection angle non-concentricity amount within 0.18°.
Databáze: Directory of Open Access Journals