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非线性隔振及时滞消振方法研究进展 被引量:7
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作者 孙秀婷 钱佳伟 +1 位作者 齐志凤 徐鉴 《力学进展》 EI CSCD 北大核心 2023年第2期308-356,共49页
振动问题与人类日常生活和科技发展紧密相关.振动不但会干扰人类的生活、影响人类健康,也会造成建筑物、机械设备和精密仪器无法正常使用甚至损坏.于是,在航空航天、汽车工程、船舶工程、大型结构及精密仪器加工等领域,人们利用弹性元... 振动问题与人类日常生活和科技发展紧密相关.振动不但会干扰人类的生活、影响人类健康,也会造成建筑物、机械设备和精密仪器无法正常使用甚至损坏.于是,在航空航天、汽车工程、船舶工程、大型结构及精密仪器加工等领域,人们利用弹性元件或控制装置形成有效的振动隔离或消除装备,有效的隔振能够提高人员和装备的安全性、稳定性、可控性和舒适性.现代结构的大型化和复杂化发展,对隔振和消振器的宽频抑振效果提出了新挑战.然而,基于线性理论的设计优化方法在分析和应用中出现了无法调和的矛盾,即,如果要拓宽隔振频带,就必须降低隔振结构的刚度,这导致结构承载能力下降.本文对典型的非线性隔振器高静低动设计方法、动力学建模、动力学分析进行了详细的综述,阐明不同机理下呈现的恢复力本构和准零刚度设计准则,在面向航空航天、精密加工、汽车船舶等领域的不同需求时,能够从动力学特征上进行选型;另外,关注到基于仿生和超结构的隔振和消振设计方法,在非线性恢复力本构的力学机理解释和调控上产生了新的问题和挑战,引发出变刚度、大变形动力学分析及其控制新方法、新策略和实验新技术的研究;最后,随着结构零部件向着轻质化和柔性化的方向发展,运动部件末端的隔振效果受限于部件的柔性,即使通过耦合多层准零刚度结构也难以实现被隔结构在空间上的快速定位,关注到时滞控制的调幅调频机理,本文对时滞抑振原理及设计方法进行讨论,提供时滞抑制柔性低频振动成功案例,为极端工况下的有效、简单、快速的主动隔振消振提供了可能性.未来,基于大数据时代的数据密集型研究范式,非线性隔振和消振技术将面向复杂工况实现更精确、更智能的控制效果,在精密仪器、航空航天等国家重大需求领域实现泛化应用. 展开更多
关键词 振动隔离 高静低动 准零刚度 非线性动力学 时滞控制
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Analysis on diffusion-induced stress for multi-layer spherical core-shell electrodes in Li-ion batteries
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作者 Siyuan Yang Chuanwei Li +4 位作者 Zhifeng Qi Lipan Xin Linan Li Shibin Wang Zhiyong Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第9期587-593,共7页
Silicon-based carbon composites are believed as promising anodes in the near future due to their outstanding specific capacity and relatively lower volume effect compared to pure silicon anodes.Herein,a multilayer sph... Silicon-based carbon composites are believed as promising anodes in the near future due to their outstanding specific capacity and relatively lower volume effect compared to pure silicon anodes.Herein,a multilayer spherical core-shell(M-SCS)electrode with a graphite framework prepared with Si@O-MCMB/C nanoparticles is developed,which aims to realize chemically/mechanically stability during the lithiation/delithiation process with high specific capacity.An electrochemical-/mechanical-coupling model for the M-SCS structure is established with various chemical/mechanical boundary conditions.The simulation of finite difference method(FDM)has been conducted based on the proposed coupling model,by which the diffusion-induced stress along both the radial and the circumferential directions is determined.Moreover,factors that influence the diffusion-induced stress of the M-SCS structure have been discussed and analyzed in detail. 展开更多
关键词 multi-layer spherical core-shell electrode diffusion-induced stress
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锂离子电池硅薄膜电极充放电形态实验研究 被引量:3
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作者 齐志凤 马伟皓 +4 位作者 杨思源 王志勇 李林安 王世斌 李传崴 《实验力学》 CSCD 北大核心 2020年第6期1041-1048,共8页
硅基电极材料因其比容量高、低脱锂电位和低成本等优点被认为是最具有潜力的下一代锂离子电池负极材料之一。然而,硅电极在嵌锂/脱锂过程中会产生巨大的体积膨胀,从而引起电极结构的力学损伤,使其力学和电化学性能大幅度衰减,最终影响... 硅基电极材料因其比容量高、低脱锂电位和低成本等优点被认为是最具有潜力的下一代锂离子电池负极材料之一。然而,硅电极在嵌锂/脱锂过程中会产生巨大的体积膨胀,从而引起电极结构的力学损伤,使其力学和电化学性能大幅度衰减,最终影响电池寿命。因此,针对硅薄膜电极在充放电过程中的变形和损伤演化行为开展研究是非常必要的。本文采用射频磁控溅射方法沉积的非晶硅薄膜作为工作电极,以CR2032型纽扣电池为原型,设计了电极可视化纽扣电池,利用激光共聚焦显微镜(Laser Scanning Confocal Microscope,LSCM)系统,结合数字图像相关(Digital Image Correlation,DIC)方法对硅薄膜电极在嵌锂/脱锂过程中的全场变形进行在线测量。基于实验数据中电极应变场和荷电状态(State of Charge,SOC)的关联关系,分析了硅电极在充放电过程中的力电耦合效应。本文结果为进一步研究硅薄膜电极在电化学循环过程中的变形及损伤提供了实验基础,对改进和优化设计新型高性能高容量的锂离子电池具有一定意义。 展开更多
关键词 锂离子电池 硅薄膜电极 嵌锂/脱锂 数字图像相关
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A novel multi-layer isolation structure for transverse stabilization inspired by neck structure 被引量:2
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作者 Xiuting Sun Zhifeng Qi Jian Xu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2022年第6期200-214,I0004,共16页
Inspired that the neck structure can stabilize the head from body movements and external dynamic vibration by the role of intervertebral disc and surrounding muscles,a novel multi-layer structure with nonlinear elasti... Inspired that the neck structure can stabilize the head from body movements and external dynamic vibration by the role of intervertebral disc and surrounding muscles,a novel multi-layer structure with nonlinear elastic components is proposed in this paper.The proposed structure is expected for loading the weight of the end effector and isolating bending vibration with lowfrequency in the range of 0.1 Hz to 1 Hz.First,considering the loading,the potential energy,restoring force,and structural configuration in axial direction are defined.Then,the dynamical restoring force and stiffness for bending are modelled for different structural parameters and configurations after the axial weight.According to the functions of the proposed structure required in applications including loading capacity and bending vibration isolation effectiveness,design criteria are carried out.Due to the realization of high-order quasi-zero stiffness property,the effective isolation band for bending vibration can be extended from about 0.08 Hz.In addition,based on the proposed design criteria,the constructed multi-layer structure displays remarkable dynamical stabilization effectiveness in ultralow frequency band.The proposed structure not only provides the biological explanations for car sickness,nausea,and airsickness of humans,but also solves the bottleneck techniques in bioinspired nonlinear isolation structural design for transverse dynamical stabilization,which has remarkable potential applications in the fields of mechanical arm,sensors in satellite etc. 展开更多
关键词 Bio-inspired structure Flexible bending structure High-static-low-frequency property High-order quasi-zero stiffness
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