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Nonlinear vibration of functionally graded graphene platelet-reinforced composite truncated conical shell using first-order shear deformation theory

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Applied Mathematics and Mechanics(English Edition) 2021年第7期42卷 981-998页

作者： Shaowu YANG yuxin hao Wei ZHANG Li YANG Lingtao LIU College of Mechanical Engineering Beijing Information Science and Technology UniversityBeijing 100192China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical EngineeringBeijing University of TechnologyBeijing 100124China

In this study,the first-order shear deformation theory(FSDT)is used to establish a nonlinear dynamic model for a conical shell truncated by a functionally graded graphene platelet-reinforced composite(FG-GPLRC).The vibration analyses of the FG-GPLRC truncated conical shell are *** the graphene platelets(GPLs)of the FG-GPLRC truncated conical shell with three different distribution patterns,the modified Halpin-Tsai model is used to calculate the effective Young’s ***’s principle,the FSDT,and the von-Karman type nonlinear geometric relationships are used to derive a system of partial differential governing equations of the FG-GPLRC truncated conical *** Galerkin method is used to obtain the ordinary differential equations of the truncated conical ***,the analytical nonlinear frequencies of the FG-GPLRC truncated conical shell are solved by the harmonic balance *** effects of the weight fraction and distribution pattern of the GPLs,the ratio of the length to the radius as well as the ratio of the radius to the thickness of the FG-GPLRC truncated conical shell on the nonlinear natural frequency characteristics are *** study culminates in the discovery of the periodic motion and chaotic motion of the FG-GPLRC truncated conical shell.

关键词： nonlinear free vibration harmonic balance method functionally graded graphene platelet-reinforced composite(FG-GPLRC) truncated conical shell chaos

Bandgaps and vibration isolation of local resonance sandwich-like plate with simply supported overhanging beam

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Applied Mathematics and Mechanics(English Edition) 2021年第11期42卷 1555-1570页

作者： Chenxu QIANG yuxin hao Wei ZHANG Jinqiang LI Shaowu YANG Yuteng CAO College of Mechanical Engineering Beijing Information Science and Technology UniversityBeijing 100192China College of Mechanical Engineering Beijing University of TechnologyBeijing 100124China College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin 150001China

The concept of local resonance phononic crystals proposed in recent years provides a new chance for theoretical and technical breakthroughs in the structural vibration *** this paper,a novel sandwich-like plate model with local resonator to acquire specific low-frequency bandgaps is *** core layer of the present local resonator is composed by the simply supported overhanging beam,linear spring and mass block,and well connected with the upper and lower surface *** simply supported overhanging beam is free at right end,and an additional linear spring is added at the left *** wave equation is established based on the Hamilton principle,and the bending wave bandgap is further *** theoretical results are verified by the COMSOL finite element *** bandgaps and vibration characteristics of the local resonance sandwich-like plate are studied in *** factors which could have effects on the bandgap characteristics,such as the structural damping,mass of vibrator,position of vibrator,bending stiffness of the beam,and the boundary conditions of the sandwich-like plates,are *** result shows that the stopband is determined by the natural frequency of the resonator,the mass ratio of the resonator,and the surface *** shows that the width of bandgap is greatly affected by the damping ratio of the ***,it can also be found that the boundary conditions can affect the isolation efficiency.

关键词： local resonance sandwich-like plate elastic wave bandgap vibration isolation

Transient Response of High Dimensional Nonlinear Dynamic System for a Rotating Cantilever Twisted Plate

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Advances in Applied Mathematics and Mechanics 2020年第6期12卷 1542-1564页

作者： yuxin hao Xiaojun Gu Wei Zhang Jie Chen College of Mechanical Engineering&Beijing Key Laboratory of Electromechanical System Measurement and Control Beijing Information Science and Technology UniversityBeijing 100192China College of Mechanical Engineering Beijing University of TechnologyBeijing 100124China Architecture and Civil Engineering Research Center Shenzhen Research InstituteCity University of Hong KongShenzhenGuangdong 518055China

Dynamic transient responses of rotating twisted plate under the air-blast loading and step loading respectively considering the geometric nonlinear relationships are investigated using classical shallow shell *** applying energy principle,a novel high dimensional nonlinear dynamic system of the rotating cantilever twisted plate is derived for the first *** use of variable mode functions by polynomial functions according to the twist angles and geometric of the plate makes it more accurate to describe the dynamic system than that using the classic cantilever beam functions and the free-free beam *** comparison researches are carried out between the present results and other literatures to validate present model,formulation and computer *** of motion describing the transient high dimensional nonlinear dynamic response are reduced to a four degree of freedom dynamic system which expressed by out-plane *** effects of twisted angle,stagger angle,rotation speed,load intensity and viscous damping on nonlinear dynamic transient responses of the twisted plate have been ***’s important to note that although the homogeneous and isotropic material is applied here,it might be helpful for laminated composite,functionally graded material as long as the equivalent material parameters are obtained.

关键词： Cantilever twisted plate rotating blast loading transient response high dimensional nonlinear dynamics

Nonlinear Dynamics of Clamped Initial Imperfect Functionally Graded Material Circular Cylindrical Shell Considering the Axisymmetric Mode

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Advances in Applied Mathematics and Mechanics 2018年第1期10卷 159-183页

作者： yuxin hao Wei Li Wei Zhang Shuangbao Li Minghui Yao College of Mechanical Engineering Beijing Information Science and Technology UniversityBeijing 100192China College of Mechanical Engineering Beijing University of TechnologyBeijing 100124China College of Science Civil Aviation University of ChinaTianjin 300300China

This paper investigates the dynamic responses of clamped-clamped functionally graded material circular cylindrical shell at both ends with small initial geometric imperfection and subjected to complex *** small initial geometric imperfection of the cylindrical shell is characterized with the shape of hyperbolic *** effects of radial harmonic excitation combined with thermal loads are *** classical theory and von-Karman type nonlinear geometric equation are applied to obtain partial differential equation of the functionally gradient material circular cylindrical shell by the Hamilton’s *** partial differential dynamic equations are truncated by the Galerkin technique,using the modal expansion with the inclusion of axisymmetric and asymmetric *** effective material properties vary in the radial direction following a power-law distribution accordancewith the volume *** effects of volume fraction indexes,ratios of thickness-radius and lengthradius on the first three dimensionless natural frequencies of the perfect cylindrical shell and its counterpart with imperfection are *** effects of radial external loads,initial geometric imperfections and volume fraction index on the nonlinear dynamic response of the clamped-clamped FGM circular cylindrical shell are discussed by numerical calculation.

关键词： Vibration circular cylindrical shell functionally graded materials geometric imperfections clamped-clamped

用渐进摄动法对具有二次非线性项的多自由度系统摄动分析

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机械工程学报 2011年第1期47卷 62-67页

作者：杨莉郝育新北京信息科技大学机电学院北京100192

考虑大挠度几何非线性和剪切变形的影响,工程中机械柔性板壳结构的非线性动力学运动控制方程经常被转化为二阶模态的、包含有二次和三次非线性项和外激励的非线性常微分方程,由于二次非线性项的存在,常用的多尺度法进行摄动分析时,需要... 详细信息

考虑大挠度几何非线性和剪切变形的影响,工程中机械柔性板壳结构的非线性动力学运动控制方程经常被转化为二阶模态的、包含有二次和三次非线性项和外激励的非线性常微分方程,由于二次非线性项的存在,常用的多尺度法进行摄动分析时,需要复杂的运算才能将其包含进来。相比之下,基于傅里叶扩展和时间尺度的渐进摄动法可以较容易地将非线性动力学微分方程中的平方项考虑进来。通过引进适当的尺度变换,利用渐进摄动法对该系统在二阶模态之间发生1:2内共振、主参数共振、1/2亚谐共振时进行摄动分析,得到自治系统下的平均方程。数值结果发现4自由度自治系统存在复杂的周期运动、倍周期运动、概周期运动。该非线性系统为量纲一后的结果,对于与该系统类似的多自由度非线性机械系统可以直接用此平均方程进行全局分叉和混沌动力学研究。

关键词：渐近摄动法内共振平均方程概周期运动

Steric hindrance modulation of hexaazatribenzanthraquinone isomers for high-capacity and wide-temperature-range aqueous proton battery

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National Science Review 2024年第4期11卷 271-282页

作者： Mingsheng Yang yuxin hao Bei Wang Yan Wang Liping Zheng Rui Li Huige Ma Xinyu Wang Xiaoming Jing Hongwei Li Mengxiao Li Zhihui Wang Yujie Dai Guangcun Shan Mingjun Hu Jun Luo Jun Yang School of Materials Science and Engineering Beihang University Beijing Institute of Nanoenergy &Nanosystems Chinese Academy of Sciences Center on Nanoenergy Research School of Physical Science & TechnologyGuangxi University School of Chemistry and Chemical Engineering Center on Nanoenergy Research Guangxi University School of Instrumentation Science and Opto-electronics Engineering Beihang University ShenSi Lab Shenzhen Institute for Advanced StudyUniversity of Electronic Science and Technology of China

Organic materials with rich active sites are good candidates of high-capacity anodes in aqueous batteries,but commonly low utilization of active sites limits their ***,two isomers,symmetric and asymmetric hexaazatribenzanthraquinone（s-HATBAQ and a-HATBAQ）,with rich active sites have been synthesized in a controllable *** has been revealed for the first time that a sulfuric acid catalyst can facilitate the stereoselective formation of *** to the reduced steric hindrance in favor of proton insertion as well as the amorphous structure conducive to electrochemical dynamics,s-HATBAQ exhibits 1.5 times larger specific capacity than ***,the electrode of s-HATBAQ with50% reduced graphene oxide（s-HATBAQ-50%rGO） delivers a record high specific capacity of405 mAh g-1in ***,the assembled MnO2//s-HATBAQ-50%rGO aqueous proton full batteries show an exceptional cycling stability at 25℃ and can maintain ～92% capacity after1000 cycles at 0.5 A g-1at-80℃.This work demonstrates the controllable synthesis of isomers,showcases a wide-temperature-range prototype proton battery and highlights the significance of precise mole cular structure modulation in organic energy storage.

关键词： stereoisomers steric effect aqueous battery super cycling stability ultra-low temperature proton battery

含MFC智能层的复合材料层合板自由振动研究

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振动．测试与诊断 2020年第1期40卷 79-88,204页

作者：赵宽飞郝育新陈静北京信息科技大学机电学院北京100192 北京信息科技大学机电系统测控北京市重点实验室北京100192

在一阶剪切变形板理论的基础上,提出一种考虑之子函数影响的位移场。根据给定的位移场,利用瑞利-里兹法和切比雪夫多项式,考虑机电耦合特性,分别求出含有智能压电宏观纤维复合材料层(macro fiber composite,简称MFC)的碳纤维增强复合材... 详细信息

在一阶剪切变形板理论的基础上,提出一种考虑之子函数影响的位移场。根据给定的位移场,利用瑞利-里兹法和切比雪夫多项式,考虑机电耦合特性,分别求出含有智能压电宏观纤维复合材料层(macro fiber composite,简称MFC)的碳纤维增强复合材料层合悬臂板在开路与通路两种电学边界条件下自由振动的固有频率,讨论不同铺层方式、宽厚比、长宽比以及不同的外电压状态下,MFC智能层对碳纤维增强复合材料层合板固有频率的影响。研究结果表明,MFC智能层对所研究系统的固有频率影响显著,可以通过控制MFC智能材料的通电电压来实现对复合材料层合板振动特性的控制。

关键词：之子函数瑞利-里兹法固有频率宏观纤维复合材料

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在校学生汉语语文词典使用情况研究

出版科学 2016年第4期24卷 33-38页

作者：郝瑜鑫华侨大学华文教育研究院厦门361021

以我国不同文化水平在校学生为被试,从学生对词典的了解、使用、评价等方面深入探讨新形势下我国学生对汉语词典的使用、需求情况。研究结论认为,我国学生词典种类使用单一;文化水平因素对学生使用词典有较大影响;在校学生普遍缺乏词典... 详细信息

以我国不同文化水平在校学生为被试,从学生对词典的了解、使用、评价等方面深入探讨新形势下我国学生对汉语词典的使用、需求情况。研究结论认为,我国学生词典种类使用单一;文化水平因素对学生使用词典有较大影响;在校学生普遍缺乏词典的基本知识和使用技能。

关键词：在校学生汉语词典使用调查

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四角点简支双稳态层合板振动特性研究

力学季刊 2021年第4期42卷 718-730页

作者：周伟兵郝育新北京信息科技大学机电学院北京100192

双稳态层合板作为一种柔性可变体结构,为实现振动状态下的构型调控,将对其开展固有振动特性的研究.本文以四角点简支约束的矩形非对称铺设双稳态板作为研究对象,运用最小势能原理、一阶剪切变形理论、以及冯卡门几何非线性位移应变关系... 详细信息

双稳态层合板作为一种柔性可变体结构,为实现振动状态下的构型调控,将对其开展固有振动特性的研究.本文以四角点简支约束的矩形非对称铺设双稳态板作为研究对象,运用最小势能原理、一阶剪切变形理论、以及冯卡门几何非线性位移应变关系,得到双稳态板的两种稳态构型.首次给出了适合于四点简支的6参数构型函数与17参数构型函数,研究对比发现对于稳态构型采用17参数的构型函数结果相对更精确;对于应用线性位移应变关系的基于任一稳态构型下振动固有特性而言,这两种构型函数得到的结果基频相差2%,其它阶次频率相差也不大.随后采用6参数构型函数得到的稳态构型研究了几何尺寸、铺层数分别对两种稳态构型固有振动特性的影响.本研究对于进一步研究该类结构动态跳变机理具有重要意义.

关键词：双稳态层合板瑞利-里兹法四角点简支振动特性