蜂窝纸板疲劳性能的研究

本文对蜂窝纸板疲劳性能进行了尝试性的试验研究,得到了蜂窝纸板的S-N曲线,同时了解了频率对蜂窝纸板疲劳寿命的影响,从而对蜂窝纸板包装运输方案的设计提供一定的依据。     

RFCCU烟机密封放空堵塞原因及处理

针对某RFCC装置烟气轮机密封放空管线堵塞情况,分析了造成堵塞的原因,认为是密封放空管线结构设计、安装配管不合理、机组维护管理工作缺失及工艺操作平稳性差等,是导致密封放空管线堵塞的主要原因。经采取优化措施后,该密封放空管线再未出现堵塞,运行正常。     

烟叶高层醇化库楼盖体系的优化

烟草片烟醇化库采用高层库房是对高效率使用土地的一种响应。通过对普通井字梁楼盖与蜂巢芯密肋楼盖在设计、施工、后期使用维护及经济性等多方面的对比,阐述在烟叶醇化高层库中采用蜂巢芯密肋楼盖结构体系的综合优势,在烟草行业库房工程中具有很好的推广价值。     

Nanomechanics of graphene

The super-high strength of single-layer graphene has attracted great interest. In practice, defects resulting from thermodynamics or introduced by fabrication, naturally or artificially, play a pivotal role in the mechanical behaviors of graphene. More importantly, high strength is just one aspect of the magnificent mechanical properties of graphene: its atomic-thin geometry not only leads to ultra-low bending rigidity, but also brings in many other unique properties of graphene in terms of mechanics in contrast to other carbon allotropes, including fullerenes and carbon nanotubes. The out-of-plane deformation is of a ‘soft’ nature, which gives rise to rich morphology and is crucial for morphology control. In this review article, we aim to summarize current theoretical advances in describing the mechanics of defects in graphene and the theory to capture the out-of-plane deformation. The structure–mechanical property relationship in graphene, in terms of its elasticity, strength, bending and wrinkling, with or without the influence of imperfections, is presented.     

Research on temperature profiles of honeycomb regenerator with asymptotic analysis

1 Introduction 1 High temperature air combustion (HTAC) [1] can offer significantly improved thermal efficiency, reduced NOx emission and uniform heat flux field. Most of HTAC use the honeycomb regenerative system to preheat the air to a temperature above…     

混凝土表面损伤的原因与防治

针对建筑工程施工过程中常见的混凝土表面损伤问题进行了分析,并对其防治措施进行了探讨。     

不规则蜂窝纸跌落碰撞的虚拟仿真分析

现有蜂窝纸制芯设备简陋,导致在生产蜂窝纸芯过程中出现不规则六边形纸芯结构的现象,运用虚拟仿真技术分析了不规则蜂窝纸的跌落碰撞过程。首先在三维软件中建立了几种相同周长但不同胶边值的蜂窝纸模型,导入有限元软件MSC.Patran/Nastran设置相应的蜂窝纸材料参数,并运用模态分析技术生成蜂窝纸柔性体文件,在动力学仿真软件MSC.adams实现刚体和柔性体结合的动态缓冲分析,最后得到相应的分析结果有助于分析不规则蜂窝纸的缓冲能力。     

Finite Element Analysis for In-Plane Crushing Behaviour of Aluminium Honeycombs

A number of finite element simulations were performed to analyze the in-plane crushing behaviour of aluminium honeycombs and the results are presented and discussed. The simulations include both X1 and X2 cases. All the analyses are quasi-static, and can be divided into three groups, which are designed to investigate the effects of cell size, foil thickness and yield stress of the foil material, respectively, on the structural response of honeycombs. The result indicates that these factors can significantly affect the plateau stresses of honeycomb cellular structures in both directions, and the plateau stresses in X2 direction are slightly smaller than those in X1 direction. The simulation results were further compared with published theoretical predictions and show higher values. The difference was then analyzed and a new expression for the plateau stress of honeycombs was suggested.     

蜂窝结构抗剪性能实验研究及其数值模拟

蜂窝结构以优异的力学性能,如比刚度大、比强度大、重量轻、良好的隔音隔热等,在建筑、工业锅炉、航空等结构中得到广泛的应用。抗剪性能是蜂窝结构主要力学性能之一,本文利用剪切实验和四点弯曲实验对PVC材料的圆形错排蜂窝结构的等效剪切模量及抗剪强度进行了实验研究,并利用有限元软件ANSYS对两种实验进行了三维有限元数值模拟。两种实验测得的等效剪切模量结果和数值模拟结果比较吻合。结果表明可以通过数值模拟对蜂窝结构的力学性能参数进行估算,并通过数值模拟为实验设计和工程实际设计理论依据和指导。     

个人通信的实现及未来前景

个人通信是以个人为对象的通信技术，是人类通信的最高目标。要实现个人通信，除应发展ＩＳＤＮ技术、智能网技术外，还要解决位置登记、跟踪交换、自动识别个人通信号码等功能。它既可用于家庭、办公室等场合，也可用于街道、商场、公共场所等低速移动场合，还可用于汽车、火车、轮船等高速移动的场合以及政府和军事部门。