资源类型

期刊论文 116

会议信息 1

会议视频 1

年份

2023 11

2022 9

2021 13

2020 6

2019 8

2018 5

2017 3

2016 4

2015 5

2014 4

2013 3

2012 1

2011 7

2010 7

2009 7

2008 6

2007 8

2006 4

2005 2

2004 1

展开 ︾

关键词

带传动 2

金属带 2

3D打印 1

Fitzhugh-Nagumo；混沌；分数阶；磁通量 1

GIC 1

Lorentz 1

WEM法 1

中子衍射，磁相图，晶体结构 1

中性原子量子计算 1

临震前磁异常 1

主动磁悬浮轴承；迭代学习控制；干扰观测器 1

二氧化钛 1

人脑功能磁共振 1

人造细菌鞭毛（ABFs） 1

仿真器 1

传动比 1

储氢合金 1

催化剂 1

光量子计算 1

展开 ︾

检索范围：

排序： 展示方式：

Rotating magnetic beacons magnetic field strength size in SAGD

Bing TU, Desheng LI, Enhuai LIN, Bin LUO, Jian HE, Lezhi YE, Jiliang LIU, Yuezhong WANG

《机械工程前沿（英文）》 2010年 第5卷 第4期   页码 446-449 doi: 10.1007/s11465-010-0113-y

摘要： Rotation magnetic beacons magnetic field strength is very important to drill parallel horizontal twin wells in steam assisted gravity drainage (SAGD). This paper analyzes a small magnet with a diameter of 25.4 mm. At each end, there is a length of 12.6 mm with permanent magnet, and in the middle, there is a length of 78 mm with magnetic materials. The magnetic field strength generated by the magnetic material of 1J12, 1J50, and 1J79 is analyzed, respectively. ANSOFT software is used to simulate the magnetic field strength generated by different magnetic materials above, which also be tested through experimental methods. The comparison of the simulation and experimental results show that experimental and simulation results are basically consistent, and the results can meet the specific requirements of engineering applications.

关键词： rotating magnetic beacons     steam assisted gravity drainage (SAGD)     ANSOFT    

HTML PDF 收藏

Nonlinear dynamic behavior of rotating blade with breathing crack

Laihao YANG, Zhu MAO, Shuming WU, Xuefeng CHEN, Ruqiang YAN

《机械工程前沿（英文）》 2021年 第16卷 第1期   页码 196-220 doi: 10.1007/s11465-020-0609-z

摘要： This study aims at investigating the nonlinear dynamic behavior of rotating blade with transverse crack. A novel nonlinear rotating cracked blade model (NRCBM), which contains the spinning softening, centrifugal stiffening, Coriolis force, and crack closing effects, is developed based on continuous beam theory and strain energy release rate method. The rotating blade is considered as a cantilever beam fixed on the rigid hub with high rotating speed, and the crack is deemed to be open and close continuously in a trigonometric function way with the blade vibration. It is verified by the comparison with a finite element-based contact crack model and bilinear model that the proposed NRCBM can well capture the dynamic characteristics of the rotating blade with breathing crack. The dynamic behavior of rotating cracked blade is then investigated with NRCBM, and the nonlinear damage indicator (NDI) is introduced to characterize the nonlinearity caused by blade crack. The results show that NDI is a distinguishable indicator for the severity level estimation of the crack in rotating blade. It is found that severe crack (i.e., a closer crack position to blade root as well as larger crack depth) is expected to heavily reduce the stiffness of rotating blade and apparently result in a lower resonant frequency. Meanwhile, the super-harmonic resonances are verified to be distinguishable indicators for diagnosing the crack existence, and the third-order super-harmonic resonances can serve as an indicator for the presence of severe crack since it only distinctly appears when the crack is severe.

关键词： rotating blade     breathing crack     nonlinear vibration     nonlinear damage indicator    

HTML PDF 收藏

New method of fault diagnosis of rotating machinery based on distance of information entropy

Houjun SU, Tielin SHI, Fei CHEN, Shuhong HUANG

《机械工程前沿（英文）》 2011年 第6卷 第2期   页码 249-253 doi: 10.1007/s11465-011-0124-3

摘要：

This paper introduces the basic conception of information fusion and some fusion diagnosis methods commonly used nowadays in rotating machinery. From the thought of the information fusion, a new quantitative feature index monitoring and diagnosing the vibration fault of rotating machinery, which is called distance of information entropy, is put forward on the basis of the singular spectrum entropy in time domain, power spectrum entropy in frequency domain, wavelet energy spectrum entropy, and wavelet space feature entropy in time-frequency domain. The mathematic deduction suggests that the conception of distance of information entropy is accordant with the maximum subordination principle in the fuzzy theory. Through calculation it has been proved that this method can effectively distinguish different fault types. Then, the accuracy of rotor fault diagnosis can be improved through the curve chart of the distance of information entropy at multi-speed.

关键词： rotating machinery     information fusion     fault diagnosis     Information entropy     distance of the information entropy    

HTML PDF 收藏

Imbalanced fault diagnosis of rotating machinery using autoencoder-based SuperGraph feature learning

《机械工程前沿（英文）》 2021年 第16卷 第4期   页码 829-839 doi: 10.1007/s11465-021-0652-4

摘要： Existing fault diagnosis methods usually assume that there are balanced training data for every machine health state. However, the collection of fault signals is very difficult and expensive, resulting in the problem of imbalanced training dataset. It will degrade the performance of fault diagnosis methods significantly. To address this problem, an imbalanced fault diagnosis of rotating machinery using autoencoder-based SuperGraph feature learning is proposed in this paper. Unsupervised autoencoder is firstly used to compress every monitoring signal into a low-dimensional vector as the node attribute in the SuperGraph. And the edge connections in the graph depend on the relationship between signals. On the basis, graph convolution is performed on the constructed SuperGraph to achieve imbalanced training dataset fault diagnosis for rotating machinery. Comprehensive experiments are conducted on a benchmarking publicized dataset and a practical experimental platform, and the results show that the proposed method can effectively achieve rotating machinery fault diagnosis towards imbalanced training dataset through graph feature learning.

关键词： imbalanced fault diagnosis     graph feature learning     rotating machinery     autoencoder    

HTML PDF 收藏

―Summary of investigations on rotating cavity at IDG, RWTH Aachen University

Dieter BOHN, Jing REN,

《能源前沿（英文）》 2009年 第3卷 第4期   页码 489-497 doi: 10.1007/s11708-009-0040-y

摘要： Annular cavities are found inside rotor shafts of turbomachines with an axial or radial throughflow of cooling air, which influences the thermal efficiency and system reliability of the gas turbines. The flow and heat transfer phenomena in those cavities should be investigated in order to minimize the thermal load and guarantee the system reliability. An experimental rig is set up in the Institute of Steam and Gas Turbines, RWTH Aachen University, to analyze the flow structure inside the rotating cavity with an axial throughflow of cooling air. The corresponding 3D numerical investigation is conducted with the in-house flow solver CHTflow, in which the Coriolis force and the buoyancy force are implemented in the time-dependent Navier-Stokes equations. Both the experimental and numerical results show that the whole flow structure rotating slower than the cavity rotating speed. The flow passing the observation windows in the experimental and numerical results indicates the quite similar trajectories. The computed sequences and periods of the vortex flow structure correspond closely with those observed in the experiment. Furthermore, the numerical analysis reveals a flow pattern changing between single pair, double pair, and triple pair vortices. It is suggested that the vortices inside the cavity are created by the gravitational buoyancy force in the investigated case, while the number and strength of the vortices are controlled mainly by the Coriolis force.

关键词： rotating cavity     buoyancy     unsteady flow    

HTML PDF 收藏

Design and realization of a remote monitoring and diagnosis and prediction system for large rotating

Shaohong WANG, Tao CHEN, Jianghong SUN

《机械工程前沿（英文）》 2010年 第5卷 第2期   页码 165-170 doi: 10.1007/s11465-009-0090-1

摘要： Traditional on-site fault diagnosis means cannot meet the needs of large rotating machinery for its performance and complexity. Remote monitoring and diagnosis technology is a new fault diagnosis mode combining computer technology, communication technology, and fault diagnosis technology. The designed remote monitoring and diagnosis and prediction system for large rotating machinery integrates the distributed resources in different places and breaks through shortcomings as the offline and decentralized information. The system can make further implementation of equipment prediction technology research based on condition monitoring and fault diagnosis, provide on-site analysis results, and carry out online actual verification of the results. The system monitors real-time condition of the equipment and achieves early fault prediction with great significance to guarantee safe operation, saves maintenance costs, and improves utilization and management of the equipment.

关键词： large rotating machinery     remote monitoring     fault diagnosis     prediction system    

HTML PDF 收藏

Convective mass transfer from a horizontal rotating cylinder in a slot air jet flow

Hongting MA , Dandan MA , Na YANG ,

《能源前沿（英文）》 2009年 第3卷 第3期   页码 289-296 doi: 10.1007/s11708-009-0019-8

摘要： The effects of air jet impinging on the mass transfer characteristics from a rotating spinning cylinder surface were experimentally investigated. The effects of rotational Reynolds number

关键词： air jet impinging     rotating cylinder     critical point     mass transfer characteristics    

HTML PDF 收藏

Metallic wastewater treatment by sulfate reduction using anaerobic rotating biological contactor reactor

Mothe Gopi Kiran, Kannan Pakshirajan, Gopal Das

《环境科学与工程前沿（英文）》 2018年 第12卷 第4期 doi: 10.1007/s11783-018-1073-4

摘要：

An-RBC reactor is highly suited to treat metallic wastewater.

Metal removal is due to sulfide precipitation via sulfate reduction by SRB.

Cu(II) removal was the best among the different heavy metals.

Maximum metal removal is achieved at low metal loading condition.

Metal removal matched well with the solubility product values of respective metal sulfide salts.

关键词： Factorial design analysis     sulfate reducing bacteria     multi-metal solution     heavy metal removal     anaerobic rotating biological contactor reactor     high metal loading.    

HTML PDF 收藏

simulated flue gas using aqueous persulfate with activation of ferrous ethylenediaminetetraacetate in the rotating

《化学科学与工程前沿（英文）》 2023年 第17卷 第4期   页码 460-469 doi: 10.1007/s11705-022-2224-5

摘要： Nitric oxide being a major gas pollutant has attracted much attention and various technologies have been developed to reduce NO emission to preserve the environment. Advanced persulfate oxidation technology is a workable and effective choice for wet flue gas denitrification due to its high efficiency and green advantages. However, NO absorption rate is limited and affected by mass transfer limitation of NO and aqueous persulfate in traditional reactors. In this study, a rotating packed bed (RPB) was employed as a gas–liquid absorption device to elevate the NO removal efficiency (ηNO) by aqueous persulfate ((NH4)2S2O8) activated by ferrous ethylenediaminetetraacetate (Fe2+-EDTA). The experimental results regarding the NO absorption were obtained by investigating the effect of various operating parameters on the removal efficiency of NO in RPB. Increasing the concentration of (NH4)2S2O8 and liquid–gas ratio could promoted the oxidation and absorption of NO while the ηNO decreased with the increase of the gas flow and NO concentration. In addition, improving the high gravity factor increased the ηNO and the total volumetric mass transfer coefficient (KGα) which raise the ηNO up to more than 75% under the investigated system. These observations proved that the RPB can enhance the gas–liquid mass transfer process in NO absorption. The correlation formula between KGα and the influencing factors was determined by regression calculation, which is used to guide the industrial scale-up application of the system in NO removal. The presence of O2 also had a negative effect on the NO removal process and through electron spin resonance spectrometer detection and product analysis, it was revealed that Fe2+-EDTA activated (NH4)2S2O8 to produce •SO4–, •OH and •O2–, played a leading role in the oxidation of NO, to produce NO3– as the final product. The obtained results demonstrated a good applicable potential of RPB/PS/Fe2+-EDTA in the removal of NO from flue gases.

关键词： rotating packed bed     Fe2+-EDTA     sulfate radical     hydroxyl radical     NO removal efficiency    

HTML PDF 收藏

Modeling and analysis of magnetic dipoles in weak magnetic field

WANG Zhaoxia, ZHANG Weimin, LIU Hongguang

《机械工程前沿（英文）》 2008年 第3卷 第2期   页码 222-225 doi: 10.1007/s11465-008-0028-z

摘要： The magnetic leakage field distribution resulting from linear defects of a tube sample in the geomagnetic field is modeled according to the magnetic dipole theory. The formula to compute the normal component of the weak magnetic field is deduced based on the spatial distribution of the magnetic dipole. The shape and characteristics of the zero line (an important criterion for magnetic memory testing) of the normal field is analyzed under different longitudinal magnetizations. Results show that the characteristics of the zero line should be considered when the metal magnetic memory testing method is used to find and locate the defect.

关键词： geomagnetic     theory     important criterion     magnetic leakage     normal component    

HTML PDF 收藏

Large-scale industrial manufacturing of carbon nanotubes in a continuous inclined mobile-bed rotating

Sophie L. Pirard, Sigrid Douven, Jean-Paul Pirard

《化学科学与工程前沿（英文）》 2017年 第11卷 第2期   页码 280-289 doi: 10.1007/s11705-017-1635-1

摘要： This article reports the different steps of the design, development and validation of a process for continuous production of carbon nanotubes (CNTs) via catalytic chemical vapor deposition from the laboratory scale to the industrial production. This process is based on a continuous inclined mobile-bed rotating reactor and very active catalysts using methane or ethylene as carbon source. The importance of modeling taking into account the hydrodynamic, physicochemical and physical phenomena that occur during CNT production in the process analysis is emphasized. The impact of this invention on the environment and human health is taken into consideration too.

关键词： carbon nanotubes     catalytic chemical vapor deposition     inclined rotating reactor     industrial process     scaling-up    

HTML PDF 收藏

Numerical analysis of rotating stall characteristics in vaneless diffuser with large width-radius ratio

GAO Chuang, GU Chuangang, WANG Tong, DAI Zhengyuan

《能源前沿（英文）》 2008年 第2卷 第4期   页码 457-460 doi: 10.1007/s11708-008-0071-9

摘要： A two-dimensional model, where the influence of wall boundary layers is neglected and inlet jet-wake velocity patterns are prescribed, was applied to simulate one vaneless diffuser with a large width-radius ratio. The impact of diffuser length, impeller blade number, etc. on the rotating stall was analyzed. Computational results show that a different mechanism does exist for diffusers with large width-radius ratios. Comparison with related conclusions and references is supportive of the model.

关键词： Comparison     Computational     two-dimensional     influence     different mechanism    

HTML PDF 收藏

Continuous size fractionation of magnetic nanoparticles by using simulated moving bed chromatography

Carsten-Rene Arlt, Dominik Brekel, Stefan Neumann, David Rafaja, Matthias Franzreb

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1346-1355 doi: 10.1007/s11705-021-2040-3

摘要： The size fractionation of magnetic nanoparticles is a technical problem, which until today can only be solved with great effort. Nevertheless, there is an important demand for nanoparticles with sharp size distributions, for example for medical technology or sensor technology. Using magnetic chromatography, we show a promising method for fractionation of magnetic nanoparticles with respect to their size and/or magnetic properties. This was achieved by passing magnetic nanoparticles through a packed bed of fine steel spheres with which they interact magnetically because single domain ferro-/ferrimagnetic nanoparticles show a spontaneous magnetization. Since the strength of this interaction is related to particle size, the principle is suitable for size fractionation. This concept was transferred into a continuous process in this work using a so-called simulated moving bed chromatography. Applying a suspension of magnetic nanoparticles within a size range from 20 to 120 nm, the process showed a separation sharpness of up to 0.52 with recovery rates of 100%. The continuous feed stream of magnetic nanoparticles could be fractionated with a space-time-yield of up to 5 mg/(L∙min). Due to the easy scalability of continuous chromatography, the process is a promising approach for the efficient fractionation of industrially relevant amounts of magnetic nanoparticles.

关键词： magnetic chromatography     simulated moving bed chromatography     magnetic nanoparticles     size fractionation    

HTML PDF 收藏

Magnetostriction varieties and stress relief caused by pulsed magnetic field

Zhipeng CAI, Xinjie DUAN, Jian LIN, Haiyan ZHAO

《机械工程前沿（英文）》 2011年 第6卷 第3期   页码 354-358 doi: 10.1007/s11465-011-0123-4

摘要：

Magnetostriction is investigated to evaluate the stress relief caused by pulsed magnetic field treatment, because this physical property is closely associated with residual stress. Magnetostriction of different stressed samples is measured in this paper. The stress variations caused by pulsed magnetic treatment are also compared. It is found that magnetostriction variations are closely associated with stress changes. Thermodynamic potential is used to find the relationship between them. Based on several assumptions, we find that the product of magnetostriction amplitude and stress magnitude is nearly a constant during magnetic field treatment, which is valuable for stress relief evaluation and optimizing processing parameters. This conclusion is testified by stress measurements, and the calculated values are in accordance with the experiment results.

关键词： magnetostriction     pulsed magnetic field treatment     stress relief    

HTML PDF 收藏

Numerical analysis of 3-D unsteady flow in a vaneless counter-rotating turbine

ZHAO Qingjun, WANG Huishe, ZHAO Xiaolu, XU Jianzhong

《能源前沿（英文）》 2007年 第1卷 第3期   页码 352-358 doi: 10.1007/s11708-007-0053-3

摘要： To reveal the unsteady flow characteristics of a vaneless counter-rotating turbine (VCRT), a three-dimensional, viscous, unsteady computational fluid dynamics (CFD) analysis was performed. The results show that unsteady simulation is superior to steady simulation because more flow characteristics can be obtained. The unsteady effects in upstream airfoil rows are weaker than those in downstream airfoil rows in the VCRT. The static pressure distribution along the span in the pressure surface of a high pressure turbine stator is more uniform than that in the suction surface. The static pressure distributions along the span in the pressure surfaces and the suction surfaces of a high pressure turbine rotor and a low pressure turbine rotor are all uneven. The numerical results also indicate that the load of a high pressure turbine rotor will increase with the increase of the span. The deviation is very big between the direction of air flow at the outlet of a high pressure turbine rotor and the axial direction. A similar result can also be obtained in the outlet of a low pressure turbine rotor. This means that the specific work of a high pressure turbine rotor and a low pressure turbine rotor is big enough to reach the design objectives.

关键词： unsteady flow     three-dimensional     pressure distribution     similar result     unsteady simulation    

HTML PDF 收藏

标题 作者 时间 类型 操作

Rotating magnetic beacons magnetic field strength size in SAGD

Bing TU, Desheng LI, Enhuai LIN, Bin LUO, Jian HE, Lezhi YE, Jiliang LIU, Yuezhong WANG

期刊论文

Nonlinear dynamic behavior of rotating blade with breathing crack

Laihao YANG, Zhu MAO, Shuming WU, Xuefeng CHEN, Ruqiang YAN

期刊论文

New method of fault diagnosis of rotating machinery based on distance of information entropy

Houjun SU, Tielin SHI, Fei CHEN, Shuhong HUANG

期刊论文

Imbalanced fault diagnosis of rotating machinery using autoencoder-based SuperGraph feature learning

期刊论文

―Summary of investigations on rotating cavity at IDG, RWTH Aachen University

Dieter BOHN, Jing REN,

期刊论文

Design and realization of a remote monitoring and diagnosis and prediction system for large rotating

Shaohong WANG, Tao CHEN, Jianghong SUN

期刊论文

Convective mass transfer from a horizontal rotating cylinder in a slot air jet flow

Hongting MA , Dandan MA , Na YANG ,

期刊论文

Metallic wastewater treatment by sulfate reduction using anaerobic rotating biological contactor reactor

Mothe Gopi Kiran, Kannan Pakshirajan, Gopal Das

期刊论文

simulated flue gas using aqueous persulfate with activation of ferrous ethylenediaminetetraacetate in the rotating

期刊论文

Modeling and analysis of magnetic dipoles in weak magnetic field

WANG Zhaoxia, ZHANG Weimin, LIU Hongguang

期刊论文

Large-scale industrial manufacturing of carbon nanotubes in a continuous inclined mobile-bed rotating

Sophie L. Pirard, Sigrid Douven, Jean-Paul Pirard

期刊论文

Numerical analysis of rotating stall characteristics in vaneless diffuser with large width-radius ratio

GAO Chuang, GU Chuangang, WANG Tong, DAI Zhengyuan

期刊论文

Continuous size fractionation of magnetic nanoparticles by using simulated moving bed chromatography

Carsten-Rene Arlt, Dominik Brekel, Stefan Neumann, David Rafaja, Matthias Franzreb

期刊论文

Magnetostriction varieties and stress relief caused by pulsed magnetic field

Zhipeng CAI, Xinjie DUAN, Jian LIN, Haiyan ZHAO

期刊论文

Numerical analysis of 3-D unsteady flow in a vaneless counter-rotating turbine

ZHAO Qingjun, WANG Huishe, ZHAO Xiaolu, XU Jianzhong

期刊论文