Dynamic modeling and coupling characteristics of rotating inclined beams with twisted-shape sections
作者机构:School of Mechanical Engineering and AutomationNortheastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of EducationNortheastern UniversityShenyang 110819China
出 版 物:《Frontiers of Mechanical Engineering》 (机械工程前沿(英文版))
年 卷 期:2020年第15卷第3期
页 面:374-389页
核心收录:
学科分类:08[工学] 080101[工学-一般力学与力学基础] 0801[工学-力学(可授工学、理学学位)]
基 金:Supported by the National Natural Science Foundation(Grant Nos.11972112 and 11772089) the Fundamental Research Funds for the Central Universities(Grant Nos.N170308028,N170306004,N2003014,and N180708009) Liaoning Revitalization Talents Program(Grant No.XLYC1807008)
主 题:elastic-support boundary pre-twisted beam semi-analytic method modal strain energy ratio torsional vibration
摘 要:In the existing literature, most studies investigated the free vibrations of a rotating pre-twisted cantilever beam;however, few considered the effect of the elastic-support boundary and the quantification of modal coupling degree among different vibration directions. In addition, Coriolis, spin softening, and centrifugal stiffening effects are not fully included in the derived equations of motion of a rotating beam in most literature, especially the centrifugal stiffening effect in torsional direction. Considering these deficiencies, this study established a coupled flapwise–chordwise–axial–torsional dynamic model of a rotating double-tapered, pre-twisted, and inclined Timoshenko beam with elastic supports based on the semi-analytic method. Then, the proposed model was verified with experiments and ANSYS models using Beam188 and Shell181 elements. Finally, the effects of setting and pre-twisted angles on the degree of coupling among flapwise, chordwise, and torsional directions were quantified via modal strain energy ratios. Results showed that 1) the appearance of torsional vibration originates from the combined effect of flapwise–torsional and chordwise–torsional couplings dependent on the Coriolis effect, and that 2) the flapwise–chordwise coupling caused by the pure pre-twisted angle is stronger than that caused by the pure setting angle.