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35th AIAA Applied Aerodynamics Conference, 2017

作者： Park, Sanghyun Chang, Kyoungsik Ko, Arim Korea Aerospace Research Institute Daejeon34133 Korea Republic of School of Mechanical Engineering The University of Ulsan Ulsan44610 Korea Republic of Department of Aero System Engineering Hanseo University TaeanChuncheongnam-do32158 Korea Republic of

ISBN: (数字)9781624105012

ISBN: (纸本)9781624105012

In the present work, numerical simulations were conducted on the scaled model of the BWB type UCAV in the subsonic region using ANSYS FLUENT V15. The prediction method was validated through comparison with experimental results and the effect of the washout wing was investigated. To consider the transitional flow phenomenon, γ transition model based on SST model was adopted. The coefficient of lift, drag and pitching moment were compared with experimental results and the pressure distribution and streamlines were investigated according to the angle of attack. The washout wing decreases the lift force but increase the lift-to-drag ratio through delay of stall and leading edge vortex’s movement to the front, also the non-linearity of the pitching moment is decreased. © 2017, American institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Angle of attack

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A FABRICATION METHOD OF HIGH-PERFORMANCE MULTISCALE SOLID OXIDE FUEL CELL VIA ADVANCED ELECTROSPRAY DEPOSITION METHOD 7

A FABRICATION METHOD OF HIGH-PERFORMANCE MULTISCALE SOLID OX...

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7th European Fuel Cell Piero Lunghi Conference, EFC 2017

作者： Shin, Sung Soo Kim, Jeong Hun Son, Ji-Won Shin, Hyun Ho Kim, Hyoungchul Choi, Mansoo Global Frontier Center for Multiscale Energy System Department of Mechanical and Aerospace Engineering Seoul National University Seoul08826 Korea Republic of Department of Mechanical and Aerospace Engineering Seoul National University Seoul08826 Korea Republic of High-Temperature Energy Materials Research Center Korea Institute of Science and Technology Seoul02792 Korea Republic of

ISBN: (纸本)9788882863241

In this study, we developed an advanced fabrication method to fabricate uniform thin film, which is hard to get from the non-vacuum system. We optimized sol-electrospray technique via electrospray deposition (ESD) method, non-vacuum process equipment. Lanthanum Strontium Cobaltite (LSC)-Ceria thin film, which we have named nano cathode functional layer (nCFL), and LSC thin film, which we have named nano adhesion layer (nAL), were fabricated on the electrolyte substrate. With optimized thin films, we fabricated three different cells, reference cell, nAL assisted cell with LSC thin film and multiscale cathode functional layer (MCFL) assisted cell with LSC-ceria thin film. Fabricated nAL assisted cell and MCFL assisted cell resulted 1099.81mW/cm2 and 1149.58mW/cm2 peak power density, which is 12.67% and 17.77% higher than the reference cell's, 976.14mW/cm2 at the 650℃ operation temperature. From the results, it is confirmed that the thin film assisted SOFC with nAL and nCFL demonstrated improved cell performances. © EFC 2017 - Proceedings of the 7th European Fuel Cell Piero Lunghi Conference.

关键词： Sol-gels

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Real-time Bezier interpolation satisfying chord error constraint for CNC tool path

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Science China(Technological Sciences) 2016年第2期59卷 203-213页

作者： FAN Wei LEE ChenHan CHEN JiHong XIAO Yao National NC System Engineering Research Center Huazhong University of Science and Technology Institute of Mechanical Manufacturing Technology China Academy of Engineering Physics Aerospace Engineering Department Zhejiang University

G01 code generated by a computer-aided manufacture （CAM） system is the most common form of tool trajeclory in computer numerical control （CNC） machining. A tool path composed of short line segments has discontinuous tangenc t and curvature, generating large fluctuations of feedrate and acceleration, which in turn produces vibration in a machine tool. To obtain a smooth tool path, many methods on tool-path smoothing have been developed. However, the shortcomings i：1 these methods exist when they are employed in a CNC system. It is difficult to simultaneously to guarantee the following requirements of CNC machining：（1） chord error should be rigidly constrained; （2） G01 points should be interpolated; （3） cur,,ature should be continuous （G2）; （4） machining should be applicable to spatial cases; （5） real-time performance of computaEion is *** on these various requirements, this study proposes an interpolation scheme using CUDlC t^ezler curves anu mciuucb illl adjustment strategy to eliminate deficiencies in the tool path. The tool path generated is G2, chord-elror-constrained, G01-point-interpolated, loop-free, and optimized for both stretch and jerk energy. The method is applicable ：o 3D cases and involves only simple algebraic computations. Thus, the algorithm can be applied to real-time CNC machining. A simulation is conducted to validate the efficiency of the algorithm. In addition, an experiment reveals its advantage over Hermite interpola- tion in surface quality and machining efficiency.

关键词： real-time CNC machining stretch energy jerk energy loop-free chord error

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Finite-time model-assisted active disturbance rejection control with a novel parameters optimizer for hypersonic reentry vehicle subject to multiple disturbances

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aerospace Science and Technology 2018年 79卷 588-600页

作者： Yue Yu Honglun Wang Na Li Huiping Zhang Zikang Su Xingling Shao School of Automation Science and Electrical Engineering Beihang University Beijing 100191 China Science and Technology on Aircraft Control Laboratory Beihang University Beijing 100191 China Unmanned System Research Institute Beihang University Beijing 100191 China School of Automation Beijing Institute of Technology Beijing 100081 China Beijing Aerospace Automatic Control Institute Beijing 100854 China Key Laboratory of Instrumentation Science & Dynamic Measurement Ministry of Education North University of China Taiyuan 030051 China National Key Laboratory for Electronic Measurement Technology School of Instrument and Electronics North University of China Taiyuan 030051 China

In this paper, a scheme which combines finite-time model-assisted active disturbance rejection control and novel greedy criterion-based salp swarm algorithm is developed for attitude tracking problem of hypersonic reentry vehicle with multiple disturbances. To simplify control structure, the control scheme is designed within the framework of active disturbance rejection control completely. To lessen tuning parameters, a sigmoid function-based tracking differentiator is employed to generate a more realizable attitude transient profile instead of utilizing conventional nonlinear tracking differentiator. Taking known model information as model-assisted term, finite-time model-assisted extended state observers are constructed to estimate the lumped disturbance in attitude and angular rate loop with employment of function fal . To achieve rapid response and strong robustness, finite-time model-assisted control laws are derived by utilizing function fhan . Finally, a novel greedy criterion-based salp swarm algorithm is used to optimize control parameters in finite-time model-assisted control laws to achieve optimal solution that minimizes the tracking error and energy consumption. Comparative simulations are conducted to illustrate the effectiveness of the proposed scheme.

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Measures to ensure the quality of space mechanisms

Lecture Notes in Mechanical Engineering

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Lecture Notes in mechanical engineering 2017年第9783319622736期 319-327页

作者： Yang, Jian-Zhong Man, Jian-Feng Wu, Qiong Zhu, Wang Beijing Institute of Spacecraft System Engineering Beijing China College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Jiangsu China School of Mechanical Engineering and Automation Beijing University of Aeronautics and Astronautics Beijing China

ISBN: (纸本)9789811322723

Space mechanisms (SMs) refer to the devices attached to the spacecraft to perform defined functions by mechanical movements. It is very important to assure the quality of SM to meet the requirements of spacecraft, because most quality defects of SMs can result in severe performance degradation or failure of the spacecraft. Based on 20 years’ experience of SMs research and development, a set of critical measures that have been found to be extremely important in quality assurance in the most demanding environments are identified. The measures can be adopted in different phases of the development process, such as design phase, manufacture phase, ground validation phase, storage and transportation phase, final assembly and integration phase, etc. It has been proved that these measures can ensure the quality of SM effectively, and can also contribute to the research and development project for new SM. © Springer International Publishing AG 2018.

关键词： Spacecraft

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Finite-Time decoupling direct control for hypersonic reentry vehicle with multiple disturbances via second-order ADRC

Finite-Time decoupling direct control for hypersonic reentry...

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2017 IEEE International Conference on Robotics and Biomimetics, ROBIO 2017

作者： Yu, Yue Wang, Honglun Li, Na Zhang, Huiping Liu, Chang School of Automation Science and Electrical Engineering Science and Technology on Aircraft Control Laboratory Beihang University Beijing 100191 China Unmanned System Research Institute Beihang University Beijing 100191 China School of Automation Beijing Institute of Technology and Beijing Aerospace Automatic Control Institute Beijing 100081 China

ISBN: (纸本)9781538637432;9781538637425

In this paper, a novel finite-Time decoupling direct control (FDDC) scheme is proposed for attitude tracking problem of hypersonic reentry vehicle (HRV) based on second-order active disturbance rejection control (SADRC). Unlike traditional control method which separates control system into outer-loop attitude control and inner-loop angular rate control, attitude is controlled by control actuator straightforward with single loop. Firstly, the attitude tracking problem is converted to the decoupling control problem of a three-input and three-output cross coupling system. In each channel, a SADRC controller, which is composed of tracking differentiator (TD), extended state observer (ESO) and nonlinear state error feedback (NLSEF), is designed to track attitude command of the corresponding channel in a finite-Time sense. Finally, the obtained virtual control input is transformed into actual control input, which acts on the HRV model. Simulations are conducted to verify the effectiveness of the proposed control scheme. © 2017 IEEE.

关键词： decoupling control extended state observer (ESO) finite-Time second-order active disturbance rejection control (SADRC)

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Sensor noise in LISA Pathfinder: An extensive in-flight review of the angular and longitudinal interferometric measurement system

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Physical Review D 2022年第8期106卷 082001-082001页

作者： M. Armano H. Audley J. Baird P. Binetruy M. Born D. Bortoluzzi N. Brandt E. Castelli A. Cavalleri A. Cesarini A. M. Cruise K. Danzmann M. de Deus Silva I. Diepholz G. Dixon R. Dolesi L. Ferraioli V. Ferroni E. D. Fitzsimons R. Flatscher M. Freschi A. García R. Gerndt L. Gesa D. Giardini F. Gibert R. Giusteri C. Grimani J. Grzymisch F. Guzman I. Harrison M-S Hartig G. Hechenblaikner G. Heinzel M. Hewitson D. Hollington D. Hoyland M. Hueller H. Inchauspé O. Jennrich P. Jetzer U. Johann B. Johlander N. Karnesis B. Kaune C. J. Killow N. Korsakova J. A. Lobo J. P. López-Zaragoza R. Maarschalkerweerd D. Mance V. Martín L. Martin-Polo F. Martin-Porqueras J. Martino P. W. McNamara J. Mendes L. Mendes N. Meshksar A. Monsky M. Nofrarias S. Paczkowski M. Perreur-Lloyd A. Petiteau E. Plagnol J. Ramos-Castro J. Reiche F. Rivas D. I. Robertson G. Russano J. Sanjuan J. Slutsky C. F. Sopuerta F. Steier T. Sumner D. Texier J. I. Thorpe D. Vetrugno S. Vitale V. Wand G. Wanner H. Ward P. J. Wass W. J. Weber L. Wissel A. Wittchen P. Zweifel European Space Technology Centre European Space Agency Keplerlaan 1 2200 AG Noordwijk Netherlands Max Planck Institute for Gravitational Physics (Albert-Einstein-Institut) 30167 Hannover Germany Leibniz Universität Hannover 30167 Hannover Germany APC Université de Paris CNRS Astroparticule et Cosmologie F-75006 Paris France Department of Industrial Engineering University of Trento via Sommarive 9 38123 Trento Italy and Trento Institute for Fundamental Physics and Application/INFN 38123 Povo Trento Italy Airbus Defence and Space Claude-Dornier-Strasse 88090 Immenstaad Germany Dipartimento di Fisica Università di Trento and Trento Institute for Fundamental Physics and Application / INFN 38123 Povo Trento Italy Istituto di Fotonica e Nanotecnologie CNR-Fondazione Bruno Kessler I-38123 Povo Trento Italy DISPEA Università di Urbino Carlo Bo Via S. Chiara 27 61029 Urbino/INFN Italy The School of Physics and Astronomy University of Birmingham B15 2TT Birmingham United Kingdom European Space Astronomy Centre European Space Agency Villanueva de la Cañada 28692 Madrid Spain Institut für Geophysik ETH Zürich Sonneggstrasse 5 CH-8092 Zürich Switzerland The UK Astronomy Technology Centre Royal Observatory Edinburgh Blackford Hill Edinburgh EH9 3HJ United Kingdom City University of Applied Sciences Flughafenallee 10 28199 Bremen Germany Institut de Ciències de l’Espai (ICE CSIC) Campus UAB Carrer de Can Magrans s/n 08193 Cerdanyola del Vallès Spain Institut d’Estudis Espacials de Catalunya (IEEC) C/ Gran Capità 2-4 08034 Barcelona Spain isardSAT SL Marie Curie 8-14 08042 Barcelona Catalonia Spain Texas A&M University 701 H.R. Bright Bldg College Station Texas 77843-3141 USA European Space Operations Centre European Space Agency 64293 Darmstadt Germany High Energy Physics Group Physics Department Imperial College London Blackett Laboratory Prince Consort Road London SW7 2BW United Kingdom Department of Mechanical and Aerospace Engineering MAE-A P.O

In a previous article [1], we have reported on the first subpicometer interferometer flown in space as part of ESA’s LISA Pathfinder mission, and have shown the residual sensor noise to be on the level of 32.0−1.7+2.4 fm/Hz. This review provides a deeper and more complete overview of the full system and its interferometric mission performance under varying operational conditions, allowing a much more detailed view on the noise model. We also include the optical measurements of rotations through differential wave front sensing (DWS), which reached a sensitivity of as good as 100 prad/Hz. We present more evidence for the long-term stability of the interferometric performance and components. This proves a solid foundation for future interferometry in space such as the LISA mission.

关键词： Gravitational waves Optical interferometry Precision measurements Satellite data analysis

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Study on break of thermal stratification in container targeted to thermodynamic vent system for future spacecraft

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IOP Conference Series: Materials Science and engineering 2019年第1期502卷

作者： Ryoji Imai Osamu Kawanami Yutaka Umemura Takehiro Himeno Course of Aerospace System Engineering Graduate School of Engineering Muroran Institute of Technology 27-1 Mizumoto-cho Muroran Hokkaido 050-8585 Japan Department of Mechanical Engineering Graduate School of Engineering University of Hyogo 2167 Syosya Himeji 271-2201 Japan Space Technology Directorate Research Unit III Aerospace Research and Development Directorate JAXA 2-1-1 Sengen Tsukuba Ibaraki 305-8505 Japan Department of Aeronautics and Astronautics The University of Tokyo 7-3-1 Hongo Bunkyo Tokyo 169-8555 Japan

In the future space exploration mission, transfer vehicle using cryogenic propellant and oxidizer will be likely operated. Thermal management systems, such as thermal insulation, pressure control, and reduction of boil off gas must be installed on transfer vehicle since cryogenic fluid has high volatile characteristics. Final target of this study is the development of thermodynamic vent system (TVS) utilizing jet mixing. Numerical simulation and ground based experiment for thermal and fluid behaviours in tank partially filled with liquid nitrogen were conducted. Thermal stratification in tank was formed by creating heat input from side wall, and change of temperature field and break of thermal stratification by jet mixing were investigated. Numerical results were evaluated by comparing with experimental results.

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Space debris impact effects on Ultrasail dynamics

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Journal of Beijing institute of Technology 2016年第S2期25卷 79-83页

作者：李延艳张景瑞赵书阁杨科莹关栋刘菲 School of Aerospace Engineering Beijing Institute of Technology The Second System Design Department of the Second Research Academy of China Aerospace Science and Industry Corporation School of Mechanical Engineering Xi'an Jiaotong University

The Ultrasail,a novel solar sail design development at the University of Illinois at UrbanaChampaign,relies in small-tip satellites to provide tension in rectangular *** the present rate of growth of orbital space debris,this paper analysis the influence of the Ultrasail dynamics on space *** main work is given the study of the whole train of thought and the latest *** was centered on deflection of the Ultrasail when the random space debris collides the thin *** on the results,appropriate measures are developed to keep the Ultrasail’s *** the film of the ultrasail is destroyed due to the collision of the space debris,the reassemble blades measures is taken to keep the Ultrasail’s balance.

关键词： collision analysis Ultrasail space debris LS-DYNA

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Sensor Noise in LISA Pathfinder: In-Flight Performance of the Optical Test Mass Readout

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Physical Review Letters 2021年第13期126卷 131103-131103页

作者： M. Armano H. Audley J. Baird P. Binetruy M. Born D. Bortoluzzi N. Brandt E. Castelli A. Cavalleri A. Cesarini A. M. Cruise K. Danzmann M. de Deus Silva I. Diepholz G. Dixon R. Dolesi L. Ferraioli V. Ferroni E. D. Fitzsimons R. Flatscher M. Freschi A. García R. Gerndt L. Gesa D. Giardini F. Gibert R. Giusteri C. Grimani J. Grzymisch F. Guzman I. Harrison M.-S. Hartig G. Heinzel M. Hewitson D. Hollington D. Hoyland M. Hueller H. Inchauspé O. Jennrich P. Jetzer U. Johann B. Johlander N. Karnesis B. Kaune C. J. Killow N. Korsakova J. A. Lobo L. Liu J. P. López-Zaragoza R. Maarschalkerweerd D. Mance V. Martín L. Martin-Polo F. Martin-Porqueras J. Martino P. W. McNamara J. Mendes L. Mendes N. Meshksar A. Monsky M. Nofrarias S. Paczkowski M. Perreur-Lloyd A. Petiteau P. Pivato E. Plagnol J. Ramos-Castro J. Reiche F. Rivas D. I. Robertson G. Russano J. Sanjuan J. Slutsky C. F. Sopuerta F. Steier T. Sumner D. Texier J. I. Thorpe D. Vetrugno S. Vitale V. Wand G. Wanner H. Ward P. J. Wass W. J. Weber L. Wissel A. Wittchen P. Zweifel European Space Technology Centre European Space Agency Keplerlaan 1 2200 AG Noordwijk The Netherlands Albert-Einstein-Institut Max-Planck-Institut für Gravitationsphysik und Leibniz Universität Hannover Callinstraße 38 30167 Hannover Germany APC Université de Paris CNRS Astroparticule et Cosmologie F-75006 Paris France Department of Industrial Engineering University of Trento via Sommarive 9 38123 Trento Italy and Trento Institute for Fundamental Physics and Application/INFN 38123 Povo Trento Italy Airbus Defence and Space Claude-Dornier-Strasse 88090 Immenstaad Germany Dipartimento di Fisica Università di Trento and Trento Institute for Fundamental Physics and Application/INFN 38123 Povo Trento Italy Istituto di Fotonica e Nanotecnologie CNR-Fondazione Bruno Kessler I-38123 Povo Trento Italy DISPEA Università di Urbino “Carlo Bo” Via Santa Chiara 27 61029 Urbino/INFN Italy The School of Physics and Astronomy University of Birmingham B15 2TT Birmingham United Kingdom European Space Astronomy Centre European Space Agency Villanueva de la Cañada 28692 Madrid Spain Institut für Geophysik ETH Zürich Sonneggstrasse 5 CH-8092 Zürich Switzerland The UK Astronomy Technology Centre Royal Observatory Edinburgh Blackford Hill Edinburgh EH9 3HJ United Kingdom City University of Applied Sciences Flughafenallee 10 28199 Bremen Germany Institut de Ciències de l’Espai (ICE CSIC) Campus UAB Carrer de Can Magrans s/n 08193 Cerdanyola del Vallès Spain Institut d’Estudis Espacials de Catalunya (IEEC) C/ Gran Capità 2-4 08034 Barcelona Spain isardSAT SL Marie Curie 8-14 08042 Barcelona Catalonia Spain Texas A&M University 701 H.R. Bright Building College Station Texas 77843-3141 USA European Space Operations Centre European Space Agency 64293 Darmstadt Germany Physics Department Blackett Laboratory High Energy Physics Group Imperial College London Prince Consort Road London SW7 2BW United Kingdom Department of Mechanical and Aerospace Engineering MAE-A

We report on the first subpicometer interferometer flown in space. It was part of ESA’s Laser Interferometer Space Antenna (LISA) Pathfinder mission and performed the fundamental measurement of the positional and angular motion of two free-falling test masses. The interferometer worked immediately, stably, and reliably from switch on until the end of the mission with exceptionally low residual noise of 32.0−1.7+2.4 fm/Hz, significantly better than required. We present an upper limit for the sensor performance at millihertz frequencies and a model for the measured sensitivity above 200 mHz.

关键词： Gravitational wave detection Laser applications Metrology Noise Data analysis Gravitational wave detectors Interferometry Satellite data analysis

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