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Modelling and simulation of flight control electromechanical actuators with special focus on model architecting, multidisciplinary effects and power flows

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Chinese Journal of Aeronautics 2017年第1期30卷 47-65页

作者： fu jian Jean-Charles Maré fu Yongling School of Mechanical Engineering and Automation Beihang University Beijing 100083 China Institut Clement Ader (CNRS UMR 5312) INSA-Toulouse Toulouse 31077 France

In the aerospace field, electromechanical actuators are increasingly being implemented in place of conventional hydraulic actuators. For safety-critical embedded actuation applications like flight controls, the use of electromechanical actuators introduces specific issues related to thermal balance, reflected inertia, parasitic motion due to compliance and response to failure. Unfortunately, the physical effects governing the actuator behaviour are multidisciplinary, coupled and nonlinear. Although numerous multi-domain and system-level simulation packages are now available on the market, these effects are rarely addressed as a whole because of a lack of scientific approaches for model architecting, multi-purpose incremental modelling and judicious model implementation. In this publication, virtual prototyping of electromechanical actuators is addressed using the Bond-Graph formalism. New approaches are proposed to enable incremental modelling,thermal balance analysis, response to free-run or jamming faults, impact of compliance on parasitic motion, and influence of temperature. A special focus is placed on friction and compliance of the mechanical transmission with fault injection and temperature dependence. Aileron actuation is used to highlight the proposals for control design, energy consumption and thermal analysis, power network pollution analysis and fault response.

关键词： Bond Graph Electro-hydrostatic actuator Electromechanical actuator More electric aircraft Modelling Power-by-wire Power loss Simulation

Review on signal-by-wire and power-by-wire actuation for more electric aircraft

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Chinese Journal of Aeronautics 2017年第3期30卷 857-870页

作者： Jean-Charles MAR jian fu Institut National des Sciences Appliquees Institut Clement Ader (CNRS UMR 5312) Toulouse 31077 France School of Mechanical Engineering and Automation Beihang University Beijing 100083 China

The huge and rapid progress in electric drives offers new opportunities to improve the performances of aircraft at all levels：fuel burn,environmental footprint,safety,integration and production,serviceability,and *** for safety-critical applications like flight-controls,landing gears,and even engines is one of the major consumers of non-propulsive *** actuation with centralized hydraulic power generation and distribution and control of power by throttling has been well established for decades,but offers a limited potential of *** this context,electric drives become more and more attractive to remove the natural drawbacks of conventional actuation and to offer new opportunities for improving *** paper takes the stock,at both the signal and power levels,of the evolution of actuation for safety-critical applications in *** focuses on the recent advances and the remaining challenges to be taken toward full electrical actuation for commercial and military aircraft,helicopters,and *** logically starts by emphasizing the specificity of safety-critical actuation for *** following section addresses in details the evolution of aerospace actuation from mechanically-signaled and hydraulically-supplied to all electric,with special emphasis on research and development programs and on solutions entered into ***,the last section reviews the challenges to be taken to generalize the use of all-electric actuators for future aircraft programs.

关键词： Actuator Aerospace Electrohydrostatic Electromechanical Hydraulic More electric aircraft Power-by-wire Signal-by-wire

Deciphering the impact of PEG antifouling layer on surface attached functional peptides in regulating cell behaviors

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Chinese Chemical Letters 2019年第12期30卷 2051-2052页

作者： fu-jian Xu Key Lab of Biomedical Materials of Natural Macromolecules Beijing University of Chemical Technology Ministry of Education.State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing Laboratory of Biomedical Materials Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology

It is highly desired to have bioactive surfaces for biomaterials and controllable interactions with *** functions were widely achieved by attaching functional peptides to the surface of *** is well known that an antifouling layer can help reducing the nonspecific cell ***,it is unclear how an antifouling PEG layer affects the function of peptides attached on material surface in controlling cell *** highlight introduced the recent JACS paper from *** and coworkers in addressing this question thoroughly.

关键词： Antifouling PEG Biomaterials Surface modification Cell behaviors

Cause analysis and solutions of water blocking damage in cracked/non-cracked tight sandstone gas reservoirs

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Petroleum Science 2021年第1期18卷 219-233页

作者： Jie Wang fu-jian Zhou Unconventional Natural Gas Institute China University of Petroleum(Beijing)Bejjing 102249China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum(Beijing)Beijing 102249China

After hydraulic fracturing treatment,a reduction in permeability caused by the invasion of fracturing fluids is an inevitable problem,which is called water blocking ***,it is important to mitigate and eliminate water blocking damage to improve the flow capacities of formation fluids and flowback rates of the fracturing ***,the steady-state core flow method cannot quickly and accurately evaluate the effects of chemical agents in enhancing the fluid flow capacities in tight *** paper introduces a time-saving and accurate method,pressure transmission test(PTT),which can quickly and quantitatively evaluate the liquid flow capacities and gas-drive flowback rates of a new ***,scanning electron microscopy(SEM)was used to analyze the damage mechanism of different fluids and the adsorption of chemical agents on the rock *** core flow experiments were used to evaluate the effects of the nanoemulsion on enhancing flowback rates in heterogeneous tight *** results show that the water blocking damage mechanisms differ in matrices and *** main channels for gas channeling are fractures in cracked cores and pores in non-cracked *** cores suffer less damage from water blocking than non-cracked cores,but have a lower potential to reduce water *** PTT and SEM results show that the permeability reduction in tight sandstones caused by invasion of external fluids can be list as guar gum fracturing fluid>slickwater>*** core flow experiments show that for low-permeability heterogenous s andstone reservoirs with a certain permeability ratio,the nanoemulsion can not only reduce reverse gas channeling degree,but also increase the flowback rate of the fracturing *** nanoemulsion system provides a new solution to mitigate and eliminate water blocking damage caused by fracturing fluids in tight sandstone gas reservoirs.

关键词： Hydraulic fracturing Water blocking damage Nanoemulsion Pressure transmission test Liquid flow capacity Flowback rate

Multi-level virtual prototyping of electromechanical actuation system for more electric aircraft

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Chinese Journal of Aeronautics 2018年第5期31卷 892-913页

作者： jian fu Jean-Charles MARE Liming YU Yongling fu School of Mechanical Engineering and Automation Beihang University Institut Clement Ader (CNRS UMR 5312) INSA-Toulouse Flying College Beihang University

Electromechanical actuators（EMAs） are becoming increasingly attractive in the field of more electric aircraft because of their outstanding benefits, which include reduced fuel burn and maintenance cost, enhanced system flexibility, and improved management of fault detection and isolation. However, electromechanical actuation raises specific issues when being used for safetycritical aerospace applications like flight controls： huge reflected inertia to load, jamming-type failure, and increase of backlash with service due to wear and local dissipation of heat losses for thermal balance. This study proposes an incremental approach for virtual prototyping of EMAs. It is driven by a model-based system engineering process in order to enable simulation-aided *** practices supported by Bond graph formalism are suggested to develop a model＇s structure efficiently and to make the model ready for use（or extension） by addressing the above mentioned issues. Physical effects are progressively introduced, and the realism of lumped-parameter models is increased step-by-step. In particular, multi-level component models are architected to ensure continuity between engineering activities. The models are implemented in the AMESim simulation environment, and simulation responses are given to illustrate how they can be used for preliminary sizing, control design, thermal balance verification, and faults to failure analysis. The proposed best practices intend to provide engineers with fast, reusable, and efficient means to assess performance virtually and enhance maturity, performance, and robustness.

关键词： Bond graph Electromechanical actuator Flight control Model-based system engi-neering More electric aircraft Power-by-wire

Influences of Inflow Condition on Non-Axisymmetric Flows in Turbine Exhaust Hoods

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Journal of Thermal Science 2008年第4期17卷 305-313页

作者： Jing-Lun fu jian-Jun LIU Institute of Engineering ThermophysicsChinese Academy of Sciences Beijing 100190 China

The complex 3D flow in a steam turbine exhaust hood model with different inlet swirl and inlet total pressure radial distributions has been simulated by employing CFX-5 and analyzed in this paper. It＇s found that the inlet tangential flow angle at hub has a negative effect on the exhaust hood performance, while a negative gradient of inlet total pressure radial distribution has a positive impact on the hood performances. It＇s also numerically con- firmed that a proper distribution of total pressure at hood inlet can successfully eliminate the negative effects caused by the inappropriate inlet swirl distribution and improve the hood aerodynamic performance.

关键词： turbine exhaust hood inflow conditions non-axisymmetric flow

System optimization-oriented spare parts dynamic configuration model for multi-echelon multi-indenture system

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Journal of Systems Engineering and Electronics 2017年第5期28卷 923-933页

作者： Minzhi Ruan Hua Li jian fu Office of Research & Development Naval University of Engineering Department of Weaponry Engineering Naval University of Engineering

In order to optimize the spares configuration project at different stages during the life cycle, the factor of time is considered to relax the assumption of the spares steady demand in multi-echelon technique for recoverable item control (METRIC) theory. According to the method of systems analysis, the dynamic palm theorem is introduced to establish the prediction model of the spares demand rate, and its main influence factors are analyzed, based on which, the spares support effectiveness evaluation index system is studied, and the system optimization-oriented spares dynamic configuration method for multi-echelon multi-indenture system is proposed. Through the analysis of the optimization algorithm, the layered marginal algorithm is designed to improve the model calculation efficiency. In a given example, the multi-stage spares configuration project during its life cycle is gotten, the research result conforms to the actual status, and it can provide a new way for the spares dynamic optimization.

关键词： system optimization spare parts dynamic demand support effectiveness multi-echelon multi-indenture layered marginal algorithm

Integrated HI emission in galaxy groups and clusters

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Research in Astronomy and Astrophysics 2017年第10期17卷 15-26页

作者： Mei Ai Ming Zhu jian fu National Astronomical Observatories Chinese Academy of Sciences Key Laboratory of Radio Astronomy Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences

The integrated HI emission from hierarchical structures such as groups and clusters of galax- ies can be detected by FAST at intermediate redshifts. Here we propose to use FAST to study the evolution of the global HI content of clusters and groups over cosmic time by measuring their integrated HI emissions. We use the Virgo Cluster as an example to estimate the detection limit of FAST, and have estimated the integration time to detect a Virgo type cluster at different redshifts （from z = 0.1 to z ---- 1.5）. We have also employed a semi-analytic model （SAM） to simulate the evolution of HI contents in galaxy clusters. Our simulations suggest that the HI mass of a Virgo-like cluster could be 2-3 times higher and the physical size could be more than 50% smaller when redshift increases from z = 0.3 to z = 1. Thus the integration time could be reduced significantly and gas rich clusters at intermediate redshifts can be detected by FAST in less than 2 hours of integration time. For the local Universe, we have also used SAM simulations to create mock catalogs of clusters to predict the outcomes from FAST all sky surveys. Comparing with the optically selected catalogs derived by cross matching the galaxy catalogs from the SDSS survey and the ALFALFA survey, we find that the HI mass distribution of the mock catalog with 20 s of integration time agrees well with that of observations. However, the mock catalog with 120 s of integration time predicts many more groups and clusters that contain a population of low mass HI galaxies not detected by the ALFALFA survey. A future deep HI blind sky survey with FAST would be able to test such prediction and set constraints on the numerical simulation models. The observational strategy and sample selections for future FAST observations of galaxy clusters at high redshifts are also discussed.

关键词： galaxy clusters -- neutral hydrogen (HI) -- galaxy evolution

Flow characteristics of integrated motor-pump assembly with phosphate ester medium for aerospace electro-hydrostatic actuators

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Chinese Journal of Aeronautics 2023年第9期36卷 392-407页

作者： jiangao ZHAO jian fu Yuchen LI Haitao QI Yan WANG Yongling fu The Laboratory of Aerospace Servo Actuation and Transmission Beijing 100191China Research Institute for Frontier Science Beihang UniversityBeijing 100191China School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China

Motor-pump assembly is the core component of the Aerospace Electro-hydrostatic Actuator(EHA).Thus,the design of the motor pump can be very challenging under conditions of high speed and wide pressure range,especially in particular working *** ultimate goal is to pursue better flow characteristics under a wide range of working *** this paper,we built a sub-model of the main friction interfaces and a model of single-shaft coaxial motor-pump assembly adopting the method of hierarchical *** experimental investigation of the output characteristics was mainly carried out in a phosphate ester medium ***,the flow characteristics were compared and analyzed with the simulation *** indicated that the flow characteristics of the motor-pump assembly could be accurately simulated by the model and quite severe in a low speed and high-pressure environment.

关键词： EHA Friction interfaces More electric aircraft Motor-pump Multidisciplinary modeling