Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 325

会议视频 17

年份

2024 1

2023 32

2022 23

2021 22

2020 20

2019 15

2018 8

2017 17

2016 9

2015 25

2014 9

2013 7

2012 10

2011 14

2010 37

2009 17

2008 13

2007 23

2006 6

2005 3

展开︾

关键词

能源 5

大直径盾构 4

农业生态工程 3

制造业 3

制造大国 3

制造强国 3

可靠性灵敏度 3

多目标优化 3

CFD 2

中国近海 2

同步注浆 2

大型化成藏 2

海上风电 2

环境 2

砂卵石地层 2

稳健设计 2

空间可展开结构 2

钢结构 2

2016年熊本地震 1

展开︾

检索范围：

排序：展示方式：

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

HTML PDF 收藏

An automated arc spray tooling system for rapid die-making of large-sized automobile body panels

HE Zhong-yun, LU Bing-heng, WANG Yi-qing, HONG Jun, TANG Yi-ping

《机械工程前沿（英文）》 2006年第1卷第2期页码 209-214 doi: 10.1007/s11465-006-0012-4

摘要： A creative robot wrist consisting of link mechanisms and a novel robot motion control method based on the cross-sectional vector contours of an STL-formatted model was proposed. By using the wrist and the control method, an industrial robot with five degrees of freedom for rapid tooling using metal arc spraying and electric brush plating techniques was developed. The wrist of the robot including a specially designed link mechanism can maintain the position of the spraying point on the surface of the master pattern whatever the orientation of the gun. Therefore, the kinematic nonlinear coupling between the position mechanism and orientation mechanism in a traditional robot can be avoided. The only input of the control system is the STL-formatted 3D CAD model of the pattern. Without the need of any manual programming, the metal arc spraying and brush plating (if necessary) processes can be performed automatically and efficiently after receiving the 3D CAD data of the pattern. Using this robot system in new car development and trial production, the cost and lead-time can be reduced substantially as compared with the conventional tool making method.

关键词： industrial position mechanism orientation surface cross-sectional

HTML PDF 收藏

大型农业生态工程的数学模型

卞有生,王天喜,陈正龙,崔斌

《中国工程科学》 2002年第4卷第7期页码 17-22

摘要：

文章在对胜利油田生态农场系统结构分析的基础上，根据农场规划目标，建立了由投入产出模型和线性规划模型相结合的经济发展数学模型。应用该模型指导农场的经济建设，取得了极好的效果，证明所建立的模型是正确的。

关键词：农业生态工程数学模型胜利油田

HTML PDF 收藏

Design of a piezoelectric transducer cylindrical phase modulator for simulating acoustic emission signals

HE Cunfu, HANG Lijun, WU Bin

《机械工程前沿（英文）》 2007年第2卷第3期页码 370-373 doi: 10.1007/s11465-007-0065-z

摘要： To conveniently carry out the pipeline leak experiment in a laboratory, leak acoustic signals are simulated by using the converse piezoelectric effect of a piezoelectric transducer (PZT) cylindrical phase modulator. On the basis of the piezoelectric equations and electromechanical equivalence principle, the transfer function of a PZT cylindrical phase modulator is delivered. A PZT cylindrical phase modulator is designed, and the numerical simulation is conducted. Results prove that the PZT cylindrical phase modulator can effectively simulate leak acoustic emission signals when the frequency is lower than 25 KHz.

关键词： KHz numerical simulation modulator cylindrical PZT

HTML PDF 收藏

A frequency error estimation for isogeometric analysis of Kirchhoff–Love cylindrical shells

《结构与土木工程前沿（英文）》 doi: 10.1007/s11709-023-0006-x

摘要： A frequency error estimation is presented for the isogeometric free vibration analysis of Kirchhoff–Love cylindrical shells using both quadratic and cubic basis functions. By analyzing the discrete isogeometric equations with the aid of harmonic wave assumption, the frequency error measures are rationally derived for the quadratic and cubic formulations for Kirchhoff–Love cylindrical shells. In particular, the governing relationship of the continuum frequency for Kirchhoff–Love cylindrical shells is naturally embedded into the frequency error measures without the need of explicit frequency expressions, which usually are not trivial for the shell problems. In accordance with these theoretical findings, the 2nd and 4th orders of frequency accuracy are attained for the isogeometric schemes using quadratic and cubic basis functions, respectively. Numerical results not only thoroughly verify the theoretical convergence rates of frequency solutions, but also manifest an excellent magnitude match between numerical and theoretical frequency errors for the isogeometric free vibration analysis of Kirchhoff–Love cylindrical shells.

关键词： isogeometric analysis Kirchhoff–Love cylindrical shell free vibration frequency error convergence

HTML PDF 收藏

Investigation on a cylindrical ultrasonic micromotor

ZHU Hua, CHEN Chao, ZHAO Chunsheng

《机械工程前沿（英文）》 2007年第2卷第4期页码 394-398 doi: 10.1007/s11465-007-0068-9

摘要： The relationship between the arrangement of ceramics and the force coefficient shows that the maximum excitation efficiency will be obtained when the ceramics are placed at the trough of the first bending mode of the stator. Therefore, a cylindrical ultrasonic micromotor with a novel stator is proposed. The prototype motor is 5 mm in diameter, 30 mm in length and 4.2 g in weight. The micromotor operates with the first bending mode at 53 kHz. Its maximum speed is 350 r/min when the drive voltage is 200 V and the stall torque reaches 2.5 mN · m. As this motor is suitable for miniaturization because of its simple structure, another cylindrical ultrasonic micromotor is developed. Piezoelectric ceramic tube is used as its stator. This micromtor is 2 mm in diameter, 7 mm in length and 0.258 g in weight. Its speed reaches 813 r/min when the drive voltage is 60 V at 75 kHz. The operation mechanism, structure and design method of these two motors are introduced.

关键词： coefficient bending kHz suitable weight

HTML PDF 收藏

Multifractal characteristics of cylindrical sludge drying

Weiyun WANG, Aimin LI,

《环境科学与工程前沿（英文）》 2009年第3卷第4期页码 464-469 doi: 10.1007/s11783-009-0040-5

摘要： This paper analyzes dewatered sludge drying using the multifractal theory. The drying rates of cylindrical sludge with equal masses but different cross-sectional diameters was studied, from which multifractal parameters such as partition function and quality exponent were obtained. The parameters acquired were used to calculate the multifractal singularity spectrum and indicate the presence of multifractal characteristics. The smaller cross-sectional diameters of the sludge were found to be non-homogeneous, and required quantitative methods to analyze.

关键词： multifractal characteristic multifractal singularity spectrum sewage sludge drying

HTML PDF 收藏

大型重载支承轴的疲劳裂纹时间序列诊断分析

李学军,宾光富,王裕清

《中国工程科学》 2006年第8卷第4期页码 50-53

摘要：

大型重载支承轴隐蔽部位由于发生不可观测的突发性疲劳断裂，严重影响正常生产，给企业带来重大经济损失；分析这类支承轴的结构特点与振动信号特征之间的关系，运用时序分析方法对振动信号进行建模，并采用残差 $σ_{a}^{2}$ 和归一化残差平方和NRSS作为识别疲劳裂纹状态的特征指标，有效诊断出了支承轴的疲劳裂纹程度。实验结果表明，采用 $σ_{a}^{2}$ 和NRSS作为特征指标的时序分析方法对大型重载支承轴隐蔽部位的疲劳裂纹状态进行诊断，比常规的时频幅值特征分析法更为敏感有效、简便易行，且具备很强的实用性。

关键词：大型重载支承轴隐蔽部位疲劳裂纹时间序列

HTML PDF 收藏

Cylindrical particulate internal flows: A review

Lizhong HUANG, Xiang GAO, Jianzhong LIN

《机械工程前沿（英文）》 2012年第7卷第4期页码 385-393 doi: 10.1007/s11465-012-0354-z

摘要：

The study of cylindrical particulate internal flows has wide industrial applicability hence received much attention. This article reviews the cylindrical particulate internal flows over the past twenty years. The research is related to the cylindrical particulate flows in the straight channel, curved channel and rotational channel. Finally, several open research issues have been identified.

关键词： cylindrical particulate flow internal flow

HTML PDF 收藏

Should medium-sized contractors still implement home-made information technologies on construction sites

Conrad BOTON, Éric ST-PIERRE, Gabriel LEFEBVRE

《工程管理前沿（英文）》 2020年第7卷第1期页码 142-158 doi: 10.1007/s42524-019-0065-9

摘要： Despite the increasing dissemination of the Building Information Modeling (BIM) approach, many firms are still far from BIM and are only starting to adopt information technologies. We conducted an ethnographic action research with an industrial partner that implements information technologies on its construction sites, with a strong preference for home-made applications. Results show that the development of such applications faces difficulties and that multiple iterations and versions are necessary before achieving the expected goals because the required competencies are lacking among internal development teams. Moreover, initial needs evolve considerably throughout the application’s development and evaluation process. However, notwithstanding the difficulties encountered during the different application development phases, the industrial partner believes the decision to be worthwhile because of the desire to have internal control over the project data and the need to consider certain specificities related to business processes.

关键词： small- and medium-sized enterprises mobile computing mobile cloud computing information technology for construction construction site ethnographic action research

HTML PDF 收藏

Predication of discharge coefficient of cylindrical weir-gate using adaptive neuro fuzzy inference systems

Abbas PARSAIE,Amir Hamzeh HAGHIABI,Mojtaba SANEIE,Hasan TORABI

《结构与土木工程前沿（英文）》 2017年第11卷第1期页码 111-122 doi: 10.1007/s11709-016-0354-x

摘要： Settlement of sediments behind weirs and accumulation of materials floating on water behind gates decreases the performance of these structures. Weir-gate is a combination of weir and gate structures which solves them Infirmities. Proposing a circular shape for crest of weirs to improve their performance, investigators have proposed cylindrical shape to improve the performance of weir-gate structure and call it cylindrical weir-gate. In this research, discharge coefficient of weir-gate was predicated using adaptive neuro fuzzy inference systems (ANFIS). To compare the performance of ANFIS with other types of soft computing techniques, multilayer perceptron neural network (MLP) was prepared as well. Results of MLP and ANFIS showed that both models have high ability for modeling and predicting discharge coefficient; however, ANFIS is a bit more accurate. The sensitivity analysis of MLP and ANFIS showed that Froude number of flow at upstream of weir and ratio of gate opening height to the diameter of weir are the most effective parameters on discharge coefficient.

关键词： weir-gate soft computing crest geometry circular crest weir cylindrical shape

HTML PDF 收藏

Preparation and crystallization kinetics of micron-sized Mg(OH)

Xingfu SONG, Kefeng TONG, Shuying SUN, Ze SUN, Jianguo YU

《化学科学与工程前沿（英文）》 2013年第7卷第2期页码 130-138 doi: 10.1007/s11705-013-1332-7

摘要： Magnesium hydroxide is an important chemical, and is usually obtained from seawater or brine via precipitation process. The particle size distribution of magnesium hydroxide has great effects on the subsequent filtration and drying processes. In this paper, micron-sized magnesium hydroxide with high purity, large particle size and low water content in filter cake was synthesized via simple wet precipitation in a mixed suspension mixed product removal (MSMPR) crystallizer. The effects of reactant concentration, residence time and impurities on the properties of magnesium hydroxide were investigated by X-Ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Malvern laser particle size analyzer. The results show that NaOH concentration and residence time have great effects on the water content and particle size of Mg(OH) . The spherical Mg(OH) with uniform diameter of about 30 μm was obtained with purity higher than 99% and water content less than 31%. Furthermore, the crystallization kinetics based on the population balance theory was studied to provide the theoretical data for industrial enlargement, and the simulation coefficients ( ) based on ASL model and C-R model are 0.9962 and 0.9972, respectively, indicating that the crystal growth rate of magnesium hydroxide can be well simulated by the size-dependent growth models.

关键词： magnesium hydroxide precipitation micron-sized crystallization kinetics

HTML PDF 收藏

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

HTML PDF 收藏

Torsional vibrations of a cylindrical foundation embedded in a saturated poroelastic half-space

Dazhi WU,Lu YU

《结构与土木工程前沿（英文）》 2015年第9卷第2期页码 194-202 doi: 10.1007/s11709-015-0292-z

摘要： Considering the interactions between an embedded foundation and saturated soil, the torsional vibrations of a cylindrical foundation embedded in a saturated poroelastic medium are analyzed in this paper. Both a rigid foundation and an elastic foundation are considered. Assuming both the side surface and the bottom surface of the foundation are perfectly bonded to soil, the reaction torques that the side soil and bottom soil acting on the foundation can be gained from basic dynamic equations of the poroelastic medium. According to the dynamic equilibrium equations of a foundation under harmonic torque, the torsional vibrations of an embedded cylindrical foundation are presented. Besides, the angular amplitude of the foundation, the equivalent stiffness and damping coefficients of the soil are expressed explicitly. Selected examples are presented to investigate the influence of relevant parameters on the torsional vibrations.

关键词： embedded foundation saturated soil rigid foundation elastic foundation torsional vibration

HTML PDF 收藏

Residual stresses in coating-based systems, part I: Mechanisms and analytical modeling

ZHANG Xiancheng, WU Yixiong, XU Binshi, WANG Haidou

《机械工程前沿（英文）》 2007年第2卷第1期页码 1-12 doi: 10.1007/s11465-007-0001-2

摘要： Thin films and multi-layered coatings comprised of different classes of materials are often used for various functional devices. The thermo-mechanical integrity of these systems is becoming a major concern and is strongly related to the residual stresses because of the fabrication processes. In this paper, the sources of the residual stresses in the coating-based systems and the concept of misfit strain were briefly reviewed. Analytical models were developed to predict the residual stresses in multi-layered film structures or coating-based systems using the force and moment balances. In addition, the residual stress distributions in the func tionally and compositionally graded coatings were also analyzed.

关键词： briefly different thermo-mechanical integrity addition residual