检索结果-内蒙古大学图书馆

CSAA/IET International Conference on Aircraft Utility Systems (AUS 2020)

作者： D. Che G. Lian K. Wang COMAC Flight Test Centre No.108 Jinwen Rd. Pudong Distict Shanghai China

Air-to-Ground Integration Flight Test Monitoring System (AIFTM), an advanced flight test monitoring system based on ground flight simulation, is introduced. The principle, application mode and implementation mode of AIFTM is elaborated. This paper introduces the application of AIFTM in the flight test subject of domestic civil aircraft In-Flight Engine Thrust Determination (IFTD), and proves its role in ensuring flight test safety and improving flight test efficiency. In the end of the paper, the application results of the system in IFTD test subject are summarized and the future development trends sketched.

关键词： aerospace computing aircraft testing aerospace simulation aerospace engines computerised monitoring mechanical engineering computing

来源：评论

学校读者我要写书评

暂无评论

System modeling and simulation for flap system power drive unit of commercial aircraft

System modeling and simulation for flap system power drive u...

引用

CSAA/IET International Conference on Aircraft Utility Systems (AUS 2020)

作者： T. Liu Y. Zhang Y. Qian J. Ju W. Yu Shanghai Aircraft Design and Research Institute Department of Flight Control System China Commercial Aircraft Corporation of China Ltd. Department of Science and Technology Management China University of Waterloo Department of Mechanical and Mechatronics Engineering Canada Shanghai Jiaotong University Department of Automation School of Electronic Information and Electrical Engineering China

This paper describes the use of mathematical modelling within flap system power driving unit for commercial aircraft. The modelling process is described from the architecture of flap system, the principle and mathematical model of electrical motors and its control loop structure. The model of power driving unit and its external load system are developed in Simulink. Basic retraction and deployment function of flap has been performed, and the response of power driving unit under a typical jam failure of the actuator is provided. This work highlights the advantages of system modelling and simulation to support the load analysis of driveline components (e.g. actuators, torque shafts, etc.) within the conceptual design phase.

关键词： mechanical engineering computing control engineering computing actuators aerospace components jamming design engineering aircraft power systems machine control computer simulation

来源：评论

学校读者我要写书评

暂无评论

Civil aircraft emergency Ram air ventilation system performacne analysis and test

Civil aircraft emergency Ram air ventilation system performa...

引用

CSAA/IET International Conference on Aircraft Utility Systems (AUS 2020)

作者： S. Xiang Z. Congxiao Shanghai Aircraft Design and Research Institute Commercial Aircraft Corporation of China Ltd Shanghai 201210 China

An emergency ram air ventilation system performance simulation model is developed based on Flowmaster platform, and a coupling CFD model of internal and external flow field of civil aircraft ram air inlet is established to get ram air total pressure performance. The results show that both of flight speed and altitude affect emergency ventilation performance; the faster speed is, the more flesh air flow; the higher altitude is, the lower flesh air flow; working condition of recirculation system will also affect the emergency ventilation flow through ventilation flow resistance, flesh air flow significantly reduced if recirculation system on. A flight test of emergency ventilation performance is carried out on a civil aircraft and analysis result is in good agreement with test results, which shows that system simulation analysis methods are reasonable and feasible. It also provides data support for the performance design and airworthiness certification of emergency ventilation system

关键词： ventilation external flows design engineering mechanical engineering computing computational fluid dynamics air aircraft testing intake systems (machines) computer simulation flow simulation

来源：评论

学校读者我要写书评

暂无评论

Emulating single point bearing faults with the use of an active magnetic bearing

引用

IET SCIENCE MEASUREMENT & TECHNOLOGY 2018年第1期12卷 39-48页

作者： Corne, Bram Vervisch, Bram Derammelaere, Stijn Knockaert, Jos Desmet, Jan Univ Ghent FEA Dept Elect Energy Syst & Automat EESA Res Grp EELAB Lemcko Graaf Karel Goedelaan 5 B-8500 Kortrijk Belgium Antwerp Univ Fac Appl Engn Dept Electromech Groenenborgerlaan 171 B-2020 Antwerp Belgium

The propagation of evolving mechanical faults in rotating electric machinery and their corresponding signatures in the machines' electrical signals is still not elucidated thoroughly. This deficiency implies serious obstructions in the development of using those signals as a complete and reliable condition monitoring technology. This study presents a new method to translate single point outer and inner race bearing faults into specific movements of the rotor with respect to the stator. The method contains the excitation of a simplified mass-spring-damper bearing model by analytical constructed fault-related force functions. Furthermore, a novel approach in order to emulate those obtained specific fault-related rotor movements with the use an experimental test setup is described, dimensioned, simulated and validated. Replacing the drive-end bearing of the induction machine under test by an active magnetic bearing creates the opportunity to continuously manipulate the rotor's position. The estimated single point bearing fault-related rotor movements serve as set-point for the magnetic bearing, resulting in the achievement of a single point bearing fault emulator with high relevance and reproducibility. This study includes experimental results of an emulated single point outer race bearing fault on an 11 kW induction machine.

关键词： asynchronous machines direction-of-arrival estimation fault diagnosis machine bearings machine testing magnetic bearings mechanical engineering computing rotors (mechanical) shock absorbers springs (mechanical) stators vibration control

来源：评论

学校读者我要写书评

暂无评论

Simultaneous bearing fault diagnosis and severity detection using a LAMSTAR network-based approach

引用

IET SCIENCE MEASUREMENT & TECHNOLOGY 2018年第7期12卷 893-901页

作者： He, Miao He, David Univ Illinois Dept Mech & Ind Engn Chicago IL 60607 USA Northeastern Univ Sch Mech Engn & Automat Shenyang Liaoning Peoples R China

Bearings are one of the most important components in many industrial machines. Effective bearing fault diagnosis and severity detection are critical for keeping the machines operate normally and safe. In this study, the problem of simultaneous bearing fault diagnosis and severity detection with deep learning is addressed. Existing solutions developed using deep learning rely on fault feature extraction using complicated signal processing techniques. They perform bearing fault diagnosis and severity detection separately and normally require extensive supervised fine tuning. This study presents an effective deep learning-based solution using a large memory storage and retrieval (LAMSTAR) neural network. The developed approach can automatically extract self-learned fault features and perform bearing fault diagnosis and severity detection simultaneously. The structure of the LAMSTAR network is determined by optimally selecting the sliding box size of the input time-frequency matrix. The effectiveness of the proposed approach is validated using data collected from rolling element bearing tests.

关键词： condition monitoring fault diagnosis feature extraction learning (artificial intelligence) machine bearings mechanical engineering computing neural nets rolling bearings signal processing

来源：评论

学校读者我要写书评

暂无评论

Directional cyclic demodulation with application to identification of rotor oil-film instability fault coupled with rub-impact

引用

IET SCIENCE MEASUREMENT & TECHNOLOGY 2018年第4期12卷 567-574页

作者： Liu, Xiaofeng Bo, Lin Luo Hongling Chongqing Univ State Key Lab Mech Transmiss Chongqing Peoples R China

In the state of oil-film instability coupled with rub-impact, the vibration signal of rotor-bearing system generally presents the weak non-linear frequency modulation (FM) features. In order to get a deep insight into the complicated FM phenomenon, the mechanism analysis is carried out on the motion model of non-linear Jeffcott rotor in oil-film instability coupled with rub-impact fault. The method of directional cyclic demodulation is proposed to extract the weak FM information embodied in the strong oil-film instability vibration. In this method, the directional cyclic autocorrelation density (DCRD) is adopted to infuse the information of two-directional vibration signals, and then is sliced along the cyclic frequency axis. The FM features and rotor motion direction are extracted from the slice of DCRD. Then the experimental research on the rotor-bearing system demonstrates the validity of the proposed method.

关键词： demodulation rotors (mechanical) mechanical stability fault diagnosis impact (mechanical) signal processing vibrations machine bearings frequency modulation oils correlation methods mechanical engineering computing directional cyclic demodulation rotor oil-film instability fault coupled identification rotor-bearing system weak nonlinear frequency modulation FM nonlinear Jeffcott rotor rub-impact fault oil-film instability vibration DCRD directional cyclic autocorrelation density two-directional vibration signal information rotor motion direction extraction

来源：评论

学校读者我要写书评

暂无评论

Detection of morphology defects in pipeline based on 3D active stereo omnidirectional vision sensor

引用

IET IMAGE PROCESSING 2018年第4期12卷 588-595页

作者： Yang, Zhongyuan Lu, Shaohui Wu, Ting Yuan, Gongping Tang, Yiping Zhejiang Inst Commun 1515 Mogan Rd Hangzhou Zhejiang Peoples R China Zhejiang Univ Technol 288 Liuhe Rd Hangzhou Zhejiang Peoples R China

There are many kinds of defects in pipes, which are difficult to detect with a low degree of automation. In this work, a novel omnidirectional vision inspection system for detection of the morphology defects is presented. An active stereo omnidirectional vision sensor is designed to obtain the texture and depth information of the inner wall of the pipeline in real time. The camera motion is estimated and the space location information of the laser points are calculated accordingly. Then, the faster region proposal convolutional neural network (Faster R-CNN) is applied to train a detection network on their image database of pipe defects. Experimental results demonstrate that system can measure and reconstruct the 3D space of pipe with high quality and the retrained Faster R-CNN achieves fine detection results in terms of both speed and accuracy.

关键词： pipelines stereo image processing image sensors image texture motion estimation learning (artificial intelligence) image reconstruction automatic optical inspection mechanical engineering computing neural nets morphology defect detection 3D active stereo omnidirectional vision sensor omnidirectional vision inspection system pipeline inner wall texture information pipeline inner wall depth information camera motion estimation laser points space location information faster region proposal convolutional neural network faster R-CNN detection network training pipe defect image database pipe 3D space reconstruction fine detection

来源：评论

学校读者我要写书评

暂无评论

Improved SNR to detect the unknown characteristic frequency by SR

引用

IET SCIENCE MEASUREMENT & TECHNOLOGY 2018年第6期12卷 795-801页

作者： Zhang, Jingling Yang, Jianhua Liu, Houguang Zhou, Dengji China Univ Min & Technol Sch Mechatron Engn Xuzhou 221116 Jiangsu Peoples R China China Univ Min & Technol Jiangsu Key Lab Mine Mech & Elect Equipment Xuzhou 221116 Jiangsu Peoples R China Shanghai Jiao Tong Univ Key Lab Power Machinery & Engn Shanghai 200240 Peoples R China Univ Michigan Dept Mech Engn Ann Arbor MI 48109 USA

Stochastic resonance (SR) is widely used in signal processing issues. The classic evaluation index of SR must know the characteristic frequency in prior. However, the accuracy frequency which needs to be detected is not known in advance. To solve this problem, the authors propose a new index, which calls improved signal-to-noise ratio (SNR) in adaptive SR. This new index is effective without knowing the accuracy characteristic frequency first. Meanwhile, the general scale transformation and random particle swarm optimisation algorithm are used to satisfy the conditions of SR and help to obtain the optimal system parameters. On the basis of this new index, the simulation and experimental bearing fault signals are both processed perfectly when compared with the classic SNR index. More importantly, it overcomes the drawbacks of the classic SNR index that the accuracy characteristic frequency must be known in advance. Therefore, these results indicate that new index has important practical values in signal processing issues.

关键词： machine bearings signal processing signal denoising mechanical engineering computing fault diagnosis stochastic processes particle swarm optimisation improved signal-to-noise ratio accuracy frequency classic evaluation index stochastic resonance unknown characteristic frequency signal processing issues advance classic SNR index experimental bearing fault signals simulation random particle swarm optimisation algorithm general scale transformation accuracy characteristic frequency adaptive SR

来源：评论

学校读者我要写书评

暂无评论

Internal combustion engine/piston integrated reluctance generator concept for vehicular applications with simple Matlab-Simulink based study

引用

IET ELECTRICAL SYSTEMS IN TRANSPORTATION 2018年第2期8卷 80-85页

作者： Masrur, Md Abul US Army RDECOM TARDEC Ground Vehicle Power & Mobil Dept Warren MI 48397 USA

This is a concept research study and describes a mechanism in which an electric power generation process is integrated within the body of the internal combustion engine structure. It includes a core made of magnetic material which is excited by a coil. This magnetic core is a part of the engine block structure itself. Concurrently, the engine piston is modified by having a disc made of magnetic material forming part of the piston structure itself. Electric power is generated by the reciprocating motion of the piston, using the principle of variation of the coil inductance with reluctance, caused by the reciprocating motion. The proposed system completely eliminates the need to have a pulley and belt mechanism. Hence there are no additional moving parts in the system, and the already existing motion of the piston is utilised in the process. In addition, multiple cylinders in the vehicle allow duplicating the generator mechanism in each of the cylinders, and thus providing redundancy and enhanced overall system reliability. The proposed system can actually be used in both generation and propulsion modes, and also allowing regenerative braking, if desired, and hence opening up possibilities for mild hybrid type of vehicular operation.

关键词： internal combustion engines reluctance generators mathematics computing digital simulation mechanical engineering computing magnetic materials magnetic cores pistons engine cylinders redundancy propulsion regenerative braking internal combustion engine/piston integrated reluctance generator concept vehicular applications Matlab–Simulink based study electric power generation process internal combustion engine structure magnetic material magnetic core engine block structure piston structure variation principle coil inductance reciprocating motion cylinders redundancy overall system reliability generation modes propulsion modes regenerative braking vehicular operation

来源：评论

学校读者我要写书评

暂无评论

Study on hydrodynamic numerical simulation and radical offset characteristics of outflow cone valve

引用

JOURNAL OF engineering-JOE 2019年第13期2019卷 231-237页

作者： Wang, Xiaojing Shen, Zhiqi Man, Guojia Liu, Hao Wang, Xin Harbin Univ Sci & Technol Sch Mech & Power Engn Harbin Heilongjiang Peoples R China Jilin Univ Sch Mech & Aerosp Engn Changchun Jilin Peoples R China

Aiming at the complicated internal flow state of hydraulic cone valve and the effect of fluid force on the performance, radial offset was seldom considered in the research of cone valve, so the inner flow field model of cone valve was established by UG software, and the mesh model was divided by ICEM CFD software. Then, the simulation calculation was carried out by FLUENT. The distribution of steady-state flow force, pressure field, and velocity field under the different opening of the cone valve was obtained. In order to verify the correctness of radial offset, the hydraulic simulation under the same working condition was carried out by AMESim software. Finally, the radial force on both sides of valve core was calculated on the basis of the pressure field on both sides of the valve core. The results show that the radial force difference on both sides of the spool is small when the valve port is small. With the increase of the valve port opening, the radial force difference between the two sides of the valve core changes larger, and finally fluctuating within a certain range. Then, the radial offset value can be calculated by the radial force formula. According to the obtained offset, the simulation and experimental study on the cavitation of the cone valve are carried out. The simulation results of radial offset are verified according to the distribution position of the cavitation, which lay the foundation for the design and performance research of the hydraulic poppet valve.

关键词： cavitation computational fluid dynamics valves hydraulic control equipment numerical analysis mechanical engineering computing hydraulic systems flow simulation hydrodynamics inner flow field model steady-state flow force pressure field radial force difference valve port opening valve core changes radial offset value radial force formula hydraulic poppet valve hydrodynamic numerical simulation radical offset characteristics outflow cone valve complicated internal flow state hydraulic cone valve

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：