Dynamic stiffness characteristics of aero-engine elastic support structure and its effects on rotor systems: mechanism and numerical and experimental studies

• Published in: Applied mathematics and mechanics Vol. 44; no. 2; pp. 221 - 236
• Main Authors: Li, Lei, Luo, Zhong, Liu, Kaining, Zhou, Jilai
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.02.2023; Springer Nature B.V; Foshan Graduate School of Innovation,Northeastern University,Foshan 528312,Guangdong Province,China; Key Laboratory of Vibration and Control of Aero-Propulsion Systems Ministry of Education of China,Northeastern University,Shenyang 110819,China; School of Mechanical Engineering and Automation,Northeastern University,Shenyang 110819,China; Key Laboratory of Vibration and Control of Aero-Propulsion Systems Ministry of Education of China,Northeastern University,Shenyang 110819,China%School of Mechanical Engineering and Automation,Northeastern University,Shenyang 110819,China
• Edition: English ed.
• Subjects: Aerospace engines; Applications of Mathematics; Classical Mechanics; Elastic supports; Excitation; Fluid- and Aerodynamics; Mathematical Modeling and Industrial Mathematics; Mathematical models; Mathematics; Mathematics and Statistics; Military helicopters; Partial Differential Equations; Rotors; Stiffness; 74H45; rotor system; dynamic stiffness; O347.6; dynamic characteristic; squirrel cage; critical speed
• ISSN: 0253-4827; 1573-2754
• DOI: 10.1007/s10483-023-2950-8

The support structure of a rotor system is subject to vibration excitation, which results in the stiffness of the support structure varying with the excitation frequency (i.e., the dynamic stiffness). However, the dynamic stiffness and its effect mechanism have been rarely incorporated in open studies of the rotor system. Therefore, this study theoretically reveals the effect mechanism of dynamic stiffness on the rotor system. Then, the numerical study and experimental verification are conducted on the dynamic stiffness characteristics of a squirrel cage, which is a common support structure for aero-engine. Moreover, the static stiffness experiment is also performed for comparison. Finally, a rotor system model considering the dynamic stiffness of the support structure is presented. The presented rotor model is used to validate the results of the theoretical analysis. The results illustrate that the dynamic stiffness reduces the critical speed of the rotor system and may lead to a new resonance.