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振动 2

碾压混凝土坝 2

区带毛细管电泳 1

压力阶梯 1

压路机工程 1

圆锥滚子轴承 1

坝面碾压 1

实时监控 1

小波包 1

工程算法 1

拱坝 1

故障诊断 1

施工仿真 1

智能碾压 1

有限时间；领导—跟随一致性；自适应滑模控制；多智能体系统 1

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波形分析 1

混沌 1

灰色模糊聚类分析 1

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Nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of profile

Walha LASSAAD, Tounsi MOHAMED, Driss YASSINE, Chaari FAKHER, Fakhfakh TAHER, Haddar MOHAMED

《机械工程前沿（英文）》 2013年 第8卷 第2期   页码 127-136 doi: 10.1007/s11465-013-0254-x

摘要：

In this paper we investigate the nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of defects. The nonlinear developed lumped-mass model includes eight degrees of freedom with two nonlinear hertzian contacts. The first one is located between cam and first roller while the second is between second roller and the sliding rod. The nonlinear dynamic behaviour is described by second order differential equations which are resolved by using the implicit Newmark algorithm combined with the Newton-Raphson iterative scheme. The influence of the cam profile error on the dynamic behaviour is also investigated.

关键词： cam     nonlinear behaviour     oscillating roller follower     profile error    

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On the improvement design of dynamic characteristics for the roller follower of a variable-speed plate

Hui Ching FAN, Hong Sen YAN

《机械工程前沿（英文）》 2012年 第7卷 第1期   页码 5-15 doi: 10.1007/s11465-012-0310-y

摘要：

Without modifying the cam contour, a cam mechanism with a variable input speed trajectory offers an alternative solution to flexibly achieve kinematic and dynamic characteristics, and then decrease the follower’s residual vibration. Firstly, the speed trajectory of cam is derived by employing Bezier curve, and motion continuity conditions are investigated. Then the motion characteristics between the plate cam and its roller follower are derived. To analyze the residual vibration, a single degree of freedom dynamic model of the elastic cam-follower system is introduced. Based on the motion equation derived from the dynamic model, the residual vibration of the follower is yielded. The design procedure to improve the kinematic and dynamic motion characteristics is presented and two design examples with discussions are provided. Finally, the simulations of the kinematic and dynamic models by ADAMS are carried out and verified that the design models as well as the performances of the mechanism are feasible.

关键词： cam mechanism     variable input speed     kinematic design     dynamic design     optimal design    

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Comparative study of oscillating flow characteristics of cryocooler regenerator at low temperatures

Yonglin JU , Qingqing SHEN ,

《能源前沿（英文）》 2009年 第3卷 第1期   页码 80-84 doi: 10.1007/s11708-009-0008-y

摘要： A brief review is presented on previous experimental results and correlations on the friction factor of cryocooler regenerators operating at oscillating flow and pulsating pressure conditions, for different mesh sizes of packed woven screens, focusing on the effects of different operating frequencies ranging from 20 to 80 Hz, at room and cryogenic temperatures. A comparison of the friction factor data with those of other studies is presented to clarify the reason for the difference. Finally, a new oscillating flow correlation of regenerators, in terms of several non-dimensional parameters, is discussed and compared.

关键词： friction factor     regenerator     oscillating flow     high frequency    

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Design and analysis of linear oscillating motor for linear pump application-magnetic field, dynamics

Zongxia JIAO,Tianyi WANG,Liang YAN

《机械工程前沿（英文）》 2016年 第11卷 第4期   页码 351-362 doi: 10.1007/s11465-016-0407-9

摘要：

A linear oscillating motor is an electromagnetic actuator that can achieve short-stroke reciprocating movement directly without auxiliary transmission mechanisms. It has been widely used in linear pump applications as the source of power and motion. However, because of the demand of high power density in a linear actuation system, the performance of linear oscillating motors has been the focus of studies and deserves further research for high power density. In this paper, a general framework of linear oscillating motor design and optimization is addressed in detail, including the electromagnetic, dynamics, and thermal aspects. First, the electromagnetic and dynamics characteristics are modeled to reveal the principle for optimization. Then, optimization and analysis on magnetic structure, resonant system, and thermal features are conducted, which provide the foundation for prototype development. Finally, experimental results are provided for validation. As a whole, this process offers complete guidance for high power density linear oscillating motors in linear pump applications.

关键词： linear oscillating motor     linear pump     magnetic field     motor optimization    

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Vibratory behaviors of Jeffcott system on cylindrical roller bearings

Hao WU, Jianwen WANG, Qi AN

《机械工程前沿（英文）》 2009年 第4卷 第3期   页码 305-309 doi: 10.1007/s11465-009-0036-7

摘要： A Jeffcott rotor system of cylindrical roller bearings is studied in detail. Its critical speed is calculated by a new calculation method with roller bearing stiffness and damping. The influences of bearing parameters, such as the roller length, rotor mass, distance between the bearings and the kinematics viscosity of oil on the system critical speed are numerically studied, and the influences of an oil film and damping on the critical speed are also studied. Regular curves of the relationship between the geometric parameters and the system critical speed are obtained. The results show that with increasing roller length and radial load, the critical speed increases; and with increasing rotor mass and the distance between the bearings and the kinematics viscosity, the critical speed decreases. This means that an oil film will decrease the critical rotational speed of the rotor system.

关键词： roller bearing     bearing-rotor system     design value     critical rotational speed    

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Temperature control of transfer roller’s bearing based on finite element analysis

Peng ZHANG, Yourong LI, Han XIAO

《机械工程前沿（英文）》 2009年 第4卷 第2期   页码 215-218 doi: 10.1007/s11465-009-0026-9

摘要： After a heat preservation cover is installed on the main rolling line, the heat dissipation environment of the transfer roller working on the heat preservation cover is changed. To ensure the normal production, a reasonable working jet capacity of the roller neck is derived. First, a globe model of the transfer roller is built for finite element analysis. Second, the sub-model of the fixed end bearing is built and the boundary condition of the sub-model is supplied by the results of the globe model. The analysis result of the sub-model shows that the temperature of the transfer roller bearing exceeds 85°C a rolling periodicity later. With finite element analysis, the heat flux is obtained and the minimum working jet capacity is derived.

关键词： transfer roller bearing     finite element analysis     sub-model     temperature control    

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Finite element modeling of counter-roller spinning for large-sized aluminum alloy cylindrical parts

Dawei ZHANG, Fan LI, Shuaipeng LI, Shengdun ZHAO

《机械工程前沿（英文）》 2019年 第14卷 第3期   页码 351-357 doi: 10.1007/s11465-019-0528-z

摘要： Counter-roller spinning (CRS), where the mandrel is replaced by rollers, is an effective means of manufacturing large-sized, thin-walled, cylindrical parts with more than 2500 mm diameter. CRS is very complex because of multi-axis rotation, multi-local loading along the circumference, and radial-axial compound deformation. Analytical or experimental methods cannot fully understand CRS. Meanwhile, numerical simulation is an adequate approach to investigate CRS with comprehensive understanding and a low cost. Thus, a finite element (FE) model of CRS was developed with the FORGE code via meshing technology, material modeling, determining the friction condition, and so on. The local fine mesh moving with the roller is one of highlights of the model. The developed 3D-FE model was validated through a CRS experiment by using a tubular blank with a 720 mm outer diameter. The developed 3D-FE model of CRS can provide a basis for parameter optimization, process control, die design, and so on. The data on force and energy predicted by the 3D-FE model can offer reasonable suggestions for determining the main mechanical parameters of CRS machines and selecting the motors. With the predicted data, an all-electric servo-drive system/machine with distributed power was designed in this work for CRS with four pairs of rollers to manufacture a large-sized, thin-walled, cylindrical part with 6000 mm diameter.

关键词： large-sized cylindrical part     counter-roller spinning     aluminum alloy     finite element method     distributed power    

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Investigation of vortical flows over oscillating body using fast Lagrangian vortex method

Baoshan ZHU ,

《能源前沿（英文）》 2009年 第3卷 第3期   页码 297-306 doi: 10.1007/s11708-009-0010-4

摘要： A computational method facilitating long-time and high-resolution unsteady vortical flows is developed with the advantages of the discrete vortex methods. Both the velocity and pressure distribution of the flow field are calculated by integral formulations in combination with a fast summation algorithm. The vorticity field is described by Lagrangian representation, which is well suited to the moving boundary. Viscosity diffusion of the vorticity is considered with the core spreading model corrected by an adaptive splitting and merging algorithm. The effectiveness of the present method is examined by comparing the numerical results of unsteady separated flows which pass a cylinder and a thin cambered blade undergoing rotational oscillations with available experimental results. Interesting results about vortex shedding patterns and lock-in characteristics are provided for the thin cambered blade.

关键词： unsteady vortical flows     fast vortex method     vortex shedding     rotational oscillation     thin cambered blade    

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Numerical simulation and analysis of periodically oscillating pressure characteristics of inviscid flow

Yan GU, Yonglin JU

《能源前沿（英文）》 2012年 第6卷 第1期   页码 21-28 doi: 10.1007/s11708-012-0173-2

摘要： Floating liquefied natural gas (LNG) plants are gaining increasing attention in offshore energy exploitation. The effects of the periodically oscillatory motion on the fluid flow in all processes on the offshore plant are very complicated and require detailed thermodynamic and hydrodynamic analyses. In this paper, numerical simulations are conducted by computational fluid dynamics (CFD) code combined with user defined function (UDF) in order to understand the periodically oscillating pressure characteristics of inviscid flow in the rolling pipe. The computational model of the circular pipe flow is established with the excitated rolling motion, at the excitated frequencies of 1–4 rad/s, and the excitated amplitudes of 3°–15°, respectively. The influences of flow velocities and excitated conditions on pressure characteristics, including mean pressure, frequency and amplitude are systematically investigated. It is found that the pressure fluctuation of the inviscid flow remains almost constant at different flow velocities. The amplitude of the pressure fluctuation increases with the increasing of the excitated amplitude, and decreases with the increasing of the excitated frequency. It is also found that the period of the pressure fluctuation varies with the excitated frequency. Furthermore, theoretical analyses of the flow in the rolling circular pipe are conducted and the results are found in qualitative agreement with the numerical simulations.

关键词： pressure fluctuation     rolling     floating production storage and offloading unit for liquefied natural gas (LNG-FPSO) offshore    

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圆锥滚子轴承振动的灰色模糊聚类分析

刘劲军,夏新涛,张立红

《中国工程科学》 2008年 第10卷 第7期   页码 112-117

摘要：

以30204型圆锥滚子轴承试验数据为基础，利用灰色模糊聚类分析方法对影响圆锥滚子轴承振动的 因素进行了综合分析，将圆锥滚子轴承各项参数按其对振动的影响分为三类：第一类对振动的影响最大，其 中包括滚子凸度、滚子直径偏差Dw 等参数；第二类对振动的影响较大，其中包括内滚道圆度，内滚道直线性 Li 等参数；第三类对振动的影响最小，其中包括内滚道波纹度，内滚道的角度偏差Δ２β 等参数。根据分类可 知，试验中圆锥滚子轴承的大部分参数都会对振动产生较大的影响。

关键词： 圆锥滚子轴承     振动     灰色模糊聚类分析    

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基于混沌振动力学的压路机工程

龙运佳,杨勇,王聪玲

《中国工程科学》 2000年 第2卷 第9期   页码 76-79

摘要：

为将混沌振动力学的理论研究转化为压路机工程的新技术成果，研制了三种混沌振动压路机（0.75t,10t,14t)，并进行了振动测试、数值仿真与压实试验，证明混沌振动压路机比普通振动压路机提高工效12.2%。其中，14t重型混沌振动压路机已用于我国西部高速公路开发。

关键词： 混沌     振动     压路机工程    

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高碾压混凝土坝智能碾压理论研究

刘东海,李丙扬,崔博

《中国工程科学》 2011年 第13卷 第12期   页码 74-79

摘要：

给出了高碾压混凝土坝智能碾压的概念及实现过程，提出了大坝实时监控和智能反馈控制的原理；在实时分析压实指标的基础上，建立了大坝压实质量多元回归模型，进而提出了碾压混凝土坝压实度全仓面实时评价方法；实现了施工过程中碾压机工作性态的自适应调整，确保碾压机速度、激振力、碾压遍数和压实厚度等全过程达标，可有效保证碾压质量，提高施工效率，为碾压混凝土坝建设质量控制提供了一条新的途径。

关键词： 碾压混凝土坝     质量控制     智能碾压     实时监控     质量实时评估    

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基于离散系统滑模控制的有限时间领导—跟随一致性 Research Article

宋睿卓1,2,邢适1,2,许镇3

《信息与电子工程前沿（英文）》 2022年 第23卷 第7期   页码 1057-1068 doi: 10.1631/FITEE.2100565

摘要： 研究了离散时间二阶多智能体系统在外部干扰约束下的有限时间领导—跟随一致性问题。首先利用自适应滑模控制理论，设计了一种新的有限时间一致性方案。自适应控制律是在传统滑模趋近律基础上改进设计的，其优点是减少抖振并保持对干扰的不变性。此外，通过给出一个离散李雅普诺夫函数，证明了离散时间二阶多智能体系统的有限时间稳定性。最后，数值模拟结果验证了理论分析的有效性。

关键词： 有限时间；领导—跟随一致性；自适应滑模控制；多智能体系统    

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高心墙堆石坝坝面碾压施工仿真理论与应用

钟登华,赵晨生,张平

《中国工程科学》 2011年 第13卷 第12期   页码 28-32

摘要：

在对高心墙堆石坝坝面碾压系统进行全面分析的基础上，提出了以填筑单元为仿真单位的碾压施工仿真理论，建立了能够反映碾压过程中不确定因素的精细化仿真模型，保证仿真贴近实际施工。研究成果在糯扎渡心墙堆石坝工程的填筑单元中得到了应用，验证了方法的可靠性，对于大坝现场碾压施工具有指导意义，为工程进度控制和管理提供了技术支持。

关键词： 高心墙堆石坝     坝面碾压     施工仿真    

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Highly active and durable Pd-Cu catalysts for oxygen reduction in alkaline exchange membrane fuel cells

ROLLER, William E. MUSTAIN

《能源前沿（英文）》 2017年 第11卷 第3期   页码 299-309 doi: 10.1007/s11708-017-0495-1

摘要： A Pd-Cu catalyst, with primary B2-type phase, supported by VulcanXC-7R carbon was synthesized via a solvothermal method. The catalysts were physically and electrochemically characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and both cyclic and linear sweep voltammetry using a rotating disk electrode (RDE). During the RDE testing, the half-wave potential of the Pd-Cu/Vulcan catalyst was 50 mV higher compared to that of commercial Pt/C catalyst for the oxygen reduction reaction (ORR) in alkaline media. The Pd-Cu/Vulcan exhibited a specific activity of 1.27 mA/cm and a mass activity of 0.59 A/mg at 0.9 V, which were 4 and 3 times greater than that of the commercial Pt/C catalyst, respectively. The Pd-Cu/Vulcan catalyst also showed higher alkaline exchange membrane fuel cell (AEMFC) performance, with operating power densities of 1100 MW/cm operating on H /O and 700 MW/cm operating on H /Air (CO -free), which were markedly higher than those of the commercial Pt/C. The Pd-Cu/Vulcan catalyst also exhibited high stability during a short-term, AEMFC durability test, with only around 11% performance loss after 30 hours of operation, an improvement over most AEMFCs reported in the literature to date.

关键词： alkaline exchange membrane (AEM)     fuel cell     Pd-Cu     oxygen reduction     high performance     water    

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标题 作者 时间 类型 操作

Nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of profile

Walha LASSAAD, Tounsi MOHAMED, Driss YASSINE, Chaari FAKHER, Fakhfakh TAHER, Haddar MOHAMED

期刊论文

On the improvement design of dynamic characteristics for the roller follower of a variable-speed plate

Hui Ching FAN, Hong Sen YAN

期刊论文

Comparative study of oscillating flow characteristics of cryocooler regenerator at low temperatures

Yonglin JU , Qingqing SHEN ,

期刊论文

Design and analysis of linear oscillating motor for linear pump application-magnetic field, dynamics

Zongxia JIAO,Tianyi WANG,Liang YAN

期刊论文

Vibratory behaviors of Jeffcott system on cylindrical roller bearings

Hao WU, Jianwen WANG, Qi AN

期刊论文

Temperature control of transfer roller’s bearing based on finite element analysis

Peng ZHANG, Yourong LI, Han XIAO

期刊论文

Finite element modeling of counter-roller spinning for large-sized aluminum alloy cylindrical parts

Dawei ZHANG, Fan LI, Shuaipeng LI, Shengdun ZHAO

期刊论文

Investigation of vortical flows over oscillating body using fast Lagrangian vortex method

Baoshan ZHU ,

期刊论文

Numerical simulation and analysis of periodically oscillating pressure characteristics of inviscid flow

Yan GU, Yonglin JU

期刊论文

圆锥滚子轴承振动的灰色模糊聚类分析

刘劲军,夏新涛,张立红

期刊论文

基于混沌振动力学的压路机工程

龙运佳,杨勇,王聪玲

期刊论文

高碾压混凝土坝智能碾压理论研究

刘东海,李丙扬,崔博

期刊论文

基于离散系统滑模控制的有限时间领导—跟随一致性

宋睿卓1,2,邢适1,2,许镇3

期刊论文

高心墙堆石坝坝面碾压施工仿真理论与应用

钟登华,赵晨生,张平

期刊论文

Highly active and durable Pd-Cu catalysts for oxygen reduction in alkaline exchange membrane fuel cells

ROLLER, William E. MUSTAIN

期刊论文