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Profibus-DP总线在印染拉幅定形机电气控制系统上的应用

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产业用纺织品 2024年第2期42卷 48-52页

作者：周振环邵阳纺织机械有限责任公司技术中心湖南邵阳422000

对印染拉幅定形机的电气控制系统进行概述。该系统采用先进的西门子Profibus-DP总线通信技术,配备丹佛斯FC302变频器构成速度闭环控制方式。通过信号级联输出方式,实现各传动单元之间的速度同步,提高速度信号的实时性和精确度。此外,介... 详细信息

对印染拉幅定形机的电气控制系统进行概述。该系统采用先进的西门子Profibus-DP总线通信技术,配备丹佛斯FC302变频器构成速度闭环控制方式。通过信号级联输出方式,实现各传动单元之间的速度同步,提高速度信号的实时性和精确度。此外,介绍了风机变频器和温控表所采用的Modbus总线通信方式,该通信方式实现了更好的设备数据整合与数据交换。

关键词：印染拉幅定形机 Profibus-DP总线速度闭环触摸屏 Modbus总线变频器信号级联可编程逻辑控制器

含切口的压电准晶组合结构界面断裂分析的辛-等几何耦合方法

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应用数学和力学 2024年第2期45卷 144-154页

作者：杨震霆王雅静聂雪阳徐新生周震寰大连理工大学工程力学系、工业装备结构分析优化与CAE软件全国重点实验室辽宁大连116024

发展了一种适用于含有切口的压电准晶/压电晶体/弹性体三材料组合结构界面断裂问题的高精度的半数值半解析方法.首先,通过引入Hamilton体系建立了三材料组合结构的Hamilton对偶方程,将原问题在传统Lagrange体系下的高阶偏微分控制方程... 详细信息

发展了一种适用于含有切口的压电准晶/压电晶体/弹性体三材料组合结构界面断裂问题的高精度的半数值半解析方法.首先,通过引入Hamilton体系建立了三材料组合结构的Hamilton对偶方程,将原问题在传统Lagrange体系下的高阶偏微分控制方程转化为低阶常微分方程组.其次,通过分离变量法求解问题对应的辛本征值和本征解,将各物理场变量利用辛级数展开形式表示.最后,将辛级数与等几何分析方法相结合,获得了辛-等几何耦合列式,直接求得切口尖端附近奇异物理场及其强度因子的解析表达式.

关键词：准晶体压电材料等几何分析 Hamilton体系 V形切口界面断裂

Accurate and straightforward symplectic approach for fracture analysis of fractional viscoelastic media

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Applied Mathematics and Mechanics(English Edition) 2022年第3期43卷 403-416页

作者： Chenghui XU Sen LENG zhenhuan zhou Xinsheng XU Zichen DENG MIIT Key Laboratory of Dynamics and Control of Complex Systems Department of Engineering MechanicsNorthwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Structure Analysis of Industrial Equipment Department of Engineering MechanicsDalian University of TechnologyDalian 116024Liaoning ProvinceChina

An accurate and straightforward symplectic method is presented for the fracture analysis of fractional two-dimensional(2D)viscoelastic *** fractional Kelvin-Zener constitutive model is used to describe the time-dependent behavior of viscoelastic *** the framework of symplectic elasticity,the governing equations in the Hamiltonian form for the frequency domain(s-domain)can be directly and rigorously *** the s-domain,the analytical solutions of the displacement and stress fields are constructed by superposing the symplectic eigensolutions without any trial function,and the explicit expressions of the intensity factors and J-integral are derived *** studies are provided to validate the accuracy and effectiveness of the present solutions.A detailed analysis is made to reveal the effects of viscoelastic parameters and applied loads on the intensity factors and J-integral.

关键词： symplectic approach viscoelastic material fractional Kelvin-Zener model crack fracture parameter

An Optimal Design of the Two-Staged Square Sectional Combined Energy Absorption Structure with Local Surface Nanocrystallization

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Acta Mechanica Solida Sinica 2021年第6期34卷 820-829页

作者： Xinsheng Xu Jianlong Qu Tong Li Zhenzhen Tong Zhen Zhao zhenhuan zhou State Key Laboratory of Structural Analysis for Industrial Equipment and Department of Engineering Mechanics Dalian University of TechnologyDalian116024China College of Locomotive and Rolling Stock Engineering Dalian Jiaotong UniversityDalian116028China

In this paper,a local surface nanocrystallization technology is used for thin-walled structures with square cross sections,and an energy absorption device of two-staged combined energy absorption structure is *** virtue of the surface nanocrystallization that enables to change the material on local positions,the structural deformation is induced and controlled to maximize the energy absorption capacity.A numerical model of the two-staged combined energy absorption structure is established,and the local surface nanocrystallization layout is *** results show that the specific energy absorption of two-staged combined structure with local surface nanocrystallization can be increased by 34.36%compared with the untreated counterpart of the same material and structural *** ratio between the first and second peak crushing forces and the energy absorption allocation ratio between the two stages can be adjusted in the ranges of 0.26–0.55 and 0.31–0.45,respectively,which can be controlled by the local surface nanocrystallization *** numerical simulation and experimental results are in good agreement,which shows that the design for energy absorption device with local surface nanocrystallization is feasible and effective.

关键词： Local surface nanocrystallization Two-staged energy absorption Square cross-sectional thin-walled structure Specific energy absorption

Modeling of C_(8) Aromatics Isomerization in a Radial Bed Reactor

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China Petroleum Processing & Petrochemical Technology 2022年第2期24卷 112-117页

作者： Gao Ninghan Tang Xiaojin zhou zhenhuan Xu Jian SINOPEC Research Institute Of Petroleum Processing Beijing 100083 China University of petroleum-Beijing Beijing 102249

Reactor models were developed to describe the isomerization reaction process of C_(8) aromatics by applying a six-component sequential reaction ***-scale experimental data were used in an axial bed reactor model,and dynamic parameters were fitted by simulated annealing *** addition,industrial data and calculated dynamic parameters were used to determine the six-component concentration distributions using a radial reactor *** influence of back-mixing on reaction performance was *** was found that the model considering back-mixing was much closer to the real industrial reaction process.

关键词： Isomerization of C_(8)aromatics reactor model radial bed reactor

An analytical symplectic approach to the vibration analysis of orthotropic graphene sheets

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Acta Mechanica Sinica 2017年第5期33卷 912-925页

作者： Xinsheng Xu Dalun Rong C.W.Lim Changyu Yang zhenhuan zhou State Key Laboratory of Structure Analysis of Industrial Equipment Department of Engineering MechanicsInternational Research Center for Computational MechanicsDalian University of Technology Department of Architecture and Civil Engineering City University of Hong Kong

A nonlocal continuum orthotropic plate model is proposed to study the vibration behavior of single-layer graphene sheets (SLGSs) using an analytical symplectic approach. A Hamiltonian system is established by introducing a total unknown vector consisting of the displacement amplitude, rotation angle, shear force, and bending moment. The high-order governing differential equation of the vibration of SLGSs is transformed into a set of ordinary differential equations in symplectic space. Exact solutions for free vibration are obtianed by the method of separation of variables without any trial shape functions and can be expanded in series of symplectic eigenfunctions. Analytical frequency equations are derived for all six possible boundary conditions. Vibration modes are expressed in terms of the symplectic eigenfunctions. In the numerical examples, comparison is presented to verify the accuracy of the proposed method. Comprehensive numerical examples for graphene sheets with Levy-type boundary conditions are given. A parametric study of the natural frequency is also included.

关键词： Hamiltonian system Analytical method Nonlocal elasticity theory Orthotropic graphene sheet Natural frequency

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Y形气动密封的弹流润滑仿真分析

液压与气动 2024年第8期48卷 154-161页

作者：冯镇军聂雪阳徐明朗梁凤林周震寰孙家斌中船重工中南装备有限责任公司湖北宜昌443005 大连理工大学力学与航空航天学院辽宁大连116024 大连理工大学化工海洋与生命学院辽宁盘锦124211

气动密封广泛应用于往复驱动机构中,其中摩擦力和泄漏量是评估密封性能的主要指标。使用弹流润滑理论建立气动往复Y形密封圈的数值分析模型,该模型耦合了流体力学、接触力学、微观变形。通过数值迭代求解获取密封区域内的油膜厚度、油... 详细信息

气动密封广泛应用于往复驱动机构中,其中摩擦力和泄漏量是评估密封性能的主要指标。使用弹流润滑理论建立气动往复Y形密封圈的数值分析模型,该模型耦合了流体力学、接触力学、微观变形。通过数值迭代求解获取密封区域内的油膜厚度、油膜压力和粗糙峰接触压力分布,以及单个行程内的流量和活塞杆表面的摩擦力。分析了Y形密封圈在不同气动条件下的弹流润滑特征以及密封性能。结果表明,增大密封压力会导致摩擦力和反向泵回率的增加,增大往复速度有利于减小泄漏量。

关键词：气动密封往复密封弹流润滑理论

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Fracture analysis of magnetoelectroelastic bimaterials with imperfect interfaces by symplectic expansion

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Applied Mathematics and Mechanics(English Edition) 2017年第8期38卷 1043-1058页

作者： Xinsheng XU Zhenzhen TONG Dalun RONG Xianhe CHENG Chenghui XU zhenhuan zhou State Key Laboratory of Structural Analysis for Industrial Equipment Department ofEngineering MechanicsInternational Center for Computational MechanicsDalian University of TechnologyDalian 116024Liaoning ProvinceChina The Forty-First Institute of China Aerospace Science and Industry Corporation Hohhot 010010China

A Hamiltonian-based analytical method is used to study the mode Ⅲ interface cracks in magnetoelectroelastic bimaterials with an imperfect interface. By introducing an unknown vector, the governing equations are reformulated in sets of first-order ordinary differential equations. Using separation of variables, eigensolutions in the symplectic space are obtained. An exact solution of the unknown vector is obtained and expressed in terms of symplectic eigensolutions. Singularities of mechanical, electric, and magnetic fields are evaluated with the generalized intensity factors. Comparisons are made to verify accuracy and stability of the proposed method. Numerical examples including mixed boundary conditions are given.

关键词： symplectic Fracture imperfect Hamiltonian ordinary singularity interfaces exact brittle verify

Inverse Load Identification in Stiffened Plate Structure Based on in situ Strain Measurement

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Structural Durability & Health Monitoring 2021年第2期15卷 85-101页

作者： Yihua Wang zhenhuan zhou Hao Xu Shuai Li Zhanjun Wu Faculty of Vehicle Engineering and Mechanics Dalian University of TechnologyDalian116024China Nantong Ocean and Coastal Engineering Research Institute Hohai UniversityNantong226000China

For practical engineering structures,it is usually difficult to measure external load distribution in a direct manner,which makes inverse load identification ***,load identification is a typical inverse problem,for which the models(e.g.,response matrix)are often ill-posed,resulting in degraded accuracy and impaired noise immunity of load *** study aims at identifying external loads in a stiffened plate structure,through comparing the effectiveness of different methods for parameter selection in regulation problems,including the Generalized Cross Validation(GCV)method,the Ordinary Cross Validation method and the truncated singular value decomposition *** demonstrated high accuracy,the GCV method is used to identify concentrated loads in three different directions(e.g.,vertical,lateral and longitudinal)exerted on a stiffened *** results show that the GCV method is able to effectively identify multi-source static loads,with relative errors less than 5%.Moreover,under the situation of swept frequency excitation,when the excitation frequency is near the natural frequency of the structure,the GCV method can achieve much higher accuracy compared with direct *** other excitation frequencies,the average recognition error of the GCV method load identification less than 10%.

关键词： Structural health monitoring load identification Tikhonov regularization generalized cross validation stiffened plate structure