Analysis and design of a novel arrayed magnetic spring with high negative stiffness for low-frequency vibration isolation. (15th February 2022)

• Record Type: Journal Article
• Authors: Wu, Jiulin; Zeng, Lizhan; Han, Bin; Zhou, Yifan; Luo, Xin; Li, Xiaoqing; Chen, Xuedong; Jiang, Wei
• Is Part Of: International journal of mechanical sciences. Volume 216(2022)
• Publication Date: 2022-02-15
• Subjects: arrayed-magnetic-spring -- negative stiffness density -- vibration isolation -- magnetic charge model -- stiffness nonlinearity; Mechanical engineering -- Periodicals; Génie mécanique -- Périodiques; Mechanical engineering; Maschinenbau; Mechanik; Zeitschrift; Periodicals; 621.05
• DOI: 10.1016/j.ijmecsci.2021.106980
• Languages: English
• ISSNs: 0020-7403

Abstract

Highlights: A novel arrayed magnetic spring with high negative stiffness density and weaker nonlinearity. Established the analytical model of the AMS-NS based on the magnetic charge model. Parametric studies on the AMS-NS are conducted for the optimal design of AMS-NS. Vibration isolator with AMS-NS is modeled and isolation performance is investigated. Experiments illustrate feasibility and validity of AMS-NS in lowering the resonance frequency. Abstract: Paralleling magnetic negative stiffness mechanism (NSM) with positive stiffness serves as an effective way to resolve the inherent contradiction between high load capacity and ultra-low frequency vibration isolation ability. Nevertheless, the stiffness nonlinearity and oversize of common magnetic NSMs restrict their further applications. In this paper, a novel compact arrayed-magnetic-spring with negative stiffness (AMS-NS) is proposed. The AMS-NS, which consists of cuboidal magnets arranged as a rectangular array, possesses high negative stiffness density and ameliorative nonlinearity. An analytical model of the AMS-NS is established based on the magnetic charge model and validated by static experiments. Parametric studies are conducted to provide guidelines for the optimal design of the AMS-NS. In addition, the nonlinear displacement transmissibility of an isolator with the AMS-NS and positive stiffness in parallel (APSP) is derived utilizing the harmonic balance method, and effect of stiffness characteristic of the AMS-NS on the isolation performance are furtherly investigated. Finally, dynamic experiments were conducted on a prototype with APSP, the results demonstrated that the proposed AMS-NS has high negative stiffness density and can effectively reduce the resonance frequency to broaden the vibration isolation band; and the analytical results showed good agreements with the experimental results. Graphical abstract: Image, graphical abstract