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《Chinese Journal of Aeronautics》 CSCD

作品数4647被引量14980H指数32
本学报1988年创刊,中国航空学会与北航大学主办,原为中文版《航空学报》选刊,1996年开始改为直接从来稿中录用文章,两刊不再重复。主要栏目有空气动力学、飞行力学、自动控制、航空电子、发动机、材料、制...查看详情>>
  • 主办单位Chinese Society of Aeronautics and Astronautics & Beihang University
  • 国际标准连续出版物号1000-9361
  • 国内统一连续出版物号11-1732/V
  • 出版周期月刊
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Guide for Authors
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作者 Editorial Office of Chinese Journal of Aeronautics 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第1期F0003-F0003,共1页
About Journal Chinese Journal of Aeronautics (CJA) is a comprehensive academic journal dealing with the fields of aeronautics and astronautics.It reports researches concerning the two fields in China and abroad to pro... About Journal Chinese Journal of Aeronautics (CJA) is a comprehensive academic journal dealing with the fields of aeronautics and astronautics.It reports researches concerning the two fields in China and abroad to promote the academic exchange.Founded in 1988 and sponsored by the Chinese Society of Aeronautics and Astronautics and Beihang University,CJA publishes papers monthly.The intended readers of the journal are specialized technical workers,teachers and students in colleges and universities and the related personnel of management,and they devote themselves to or are interested in the scientific research,teaching,design,experimentation,manufacture or application in the industries of aeronautics and astronautics. 展开更多
关键词 dealing concerning EXCHANGE
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Guide for Authors
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作者 Editorial Office of Chinese Journal of Aeronautics 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第4期F0003-F0003,共1页
About Journal Chinese Journal of Aeronautics (CJA) is a comprehensive academic journal dealing with the fields of aeronautics and astronautics. It reports researches concerning the two fields in China and abroad to pr... About Journal Chinese Journal of Aeronautics (CJA) is a comprehensive academic journal dealing with the fields of aeronautics and astronautics. It reports researches concerning the two fields in China and abroad to promote the academic exchange. 展开更多
关键词 dealing JOURNAL concerning
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Experimental and numerical investigation of two blended blade and endwall configurations
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作者 Tongtong MENG Xin LI +1 位作者 Ling ZHOU Lucheng JI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第9期150-163,共14页
The Blended Blade and Endwall(BBEW)technique has proven to be effective in control-ling the intersection of boundary layer in corner region of the compressor endwall.In this study,the experiment and analysis of two di... The Blended Blade and Endwall(BBEW)technique has proven to be effective in control-ling the intersection of boundary layer in corner region of the compressor endwall.In this study,the experiment and analysis of two different BBEW designs are emphasized.First,based on a linear cas-cade with 0.7 Mach number inflow,two different configurations,BBEW 1 and BBEW 2,are well conducted.Then,according to the experimental result,control effects of these two BBEW configu-rations are validated and compared subsequently under various working conditions.The results demonstrate a reduction in total pressure loss of 12.8%and 29%at the design point for BBEW 1 and BBEW 2,respectively.Consequently,the BBEW technique proves effective in suppressing the development of the boundary layer and preventing corner separation.Followed by detailed numerical analysis,improvements around the corner region,especially for the boundary layer,are extracted to show the mechanisms and distinctions between the two configurations.The results indicate that BBEW 1 significantly restrains the development of boundary layer before separation occurs,while BBEW 2 directly controls the strength and scale of the corner separation. 展开更多
关键词 Aerodynamic Computational fluid dynamic Experiment Corner separation Blended Blade and Endwall(BBEW)
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Turbo-shaft engine adaptive neural network control based on nonlinear state space equation
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作者 Ziyu GU Qiuhong LI +3 位作者 Shuwei PANG Wenxiang ZHOU Jichang WU Chenyang ZHANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第4期493-507,共15页
Intelligent Adaptive Control(AC) has remarkable advantages in the control system design of aero-engine which has strong nonlinearity and uncertainty. Inspired by the Nonlinear Autoregressive Moving Average(NARMA)-L2 a... Intelligent Adaptive Control(AC) has remarkable advantages in the control system design of aero-engine which has strong nonlinearity and uncertainty. Inspired by the Nonlinear Autoregressive Moving Average(NARMA)-L2 adaptive control, a novel Nonlinear State Space Equation(NSSE) based Adaptive neural network Control(NSSE-AC) method is proposed for the turbo-shaft engine control system design. The proposed NSSE model is derived from a special neural network with an extra layer, and the rotor speed of the gas turbine is taken as the main state variable which makes the NSSE model be able to capture the system dynamic better than the NARMA-L2 model. A hybrid Recursive Least-Square and Levenberg-Marquardt(RLS-LM) algorithm is advanced to perform the online learning of the neural network, which further enhances both the accuracy of the NSSE model and the performance of the adaptive controller. The feedback correction is also utilized in the NSSE-AC system to eliminate the steady-state tracking error. Simulation results show that, compared with the NARMA-L2 model, the NSSE model of the turboshaft engine is more accurate. The maximum modeling error is decreased from 5.92% to 0.97%when the LM algorithm is introduced to optimize the neural network parameters. The NSSE-AC method can not only achieve a better main control loop performance than the traditional controller but also limit all the constraint parameters efficiently with quick and accurate switching responses even if component degradation exists. Thus, the effectiveness of the NSSE-AC method is validated. 展开更多
关键词 Adaptive control systems Turbo-shaft engine Neural network Nonlinear state space equation NARMA-L2
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A reduced-order model for fast predicting ionized flows of hypersonic vehicles along flight trajectory
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作者 Jingchao ZHANG Chunsheng NIE +1 位作者 Jinsheng CAI Shucheng PAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第1期89-105,共17页
An improved Reduced-Order Model(ROM)is proposed based on a flow-solution preprocessing operation and a fast sampling strategy to efficiently and accurately predict ionized hypersonic flows.This ROM is generated in low... An improved Reduced-Order Model(ROM)is proposed based on a flow-solution preprocessing operation and a fast sampling strategy to efficiently and accurately predict ionized hypersonic flows.This ROM is generated in low-dimensional space by performing the Proper Orthogonal Decomposition(POD)on snapshots and is coupled with the Radial Basis Function(RBF)to achieve fast prediction speed.However,due to the disparate scales in the ionized flow field,the conventional ROM usually generates spurious negative errors.Here,this issue is addressed by performing flow-solution preprocessing in logarithmic space to improve the conventional ROM.Then,extra orthogonal polynomials are introduced in the RBF interpolation to achieve additional improvement of the prediction accuracy.In addition,to construct high-efficiency snapshots,a trajectory-constrained adaptive sampling strategy based on convex hull optimization is developed.To evaluate the performance of the proposed fast prediction method,two hypersonic vehicles with classic configurations,i.e.a wave-rider and a reentry capsule,are used to validate the proposed method.Both two cases show that the proposed fast prediction method has high accuracy near the vehicle surface and the free-stream region where the flow field is smooth.Compared with the conventional ROM prediction,the prediction results are significantly improved by the proposed method around the discontinuities,e.g.the shock wave and the ionized layer.As a result,the proposed fast prediction method reduces the error of the conventional ROM by at least 45%,with a speedup of approximately 2.0×105compared to the Computational Fluid Dynamic(CFD)simulations.These test cases demonstrate that the method developed here is efficient and accurate for predicting ionized hypersonic flows. 展开更多
关键词 Reduced-order model Radial basis function Constrained sampling Transfer function Fast flow prediction Ionized hypersonic flows
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Reliability analysis of multimodal scene matching based on correlation peaks
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作者 Zhirui YU Bai ZHU +1 位作者 Zhiqiang HAN Yuanxin YE 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第9期433-447,共15页
The navigation system plays a pivotal role in guiding aircraft along designated routes,ensuring precise and punctual arrival at destinations.The integration of scene matching with an inertial navigation system enhance... The navigation system plays a pivotal role in guiding aircraft along designated routes,ensuring precise and punctual arrival at destinations.The integration of scene matching with an inertial navigation system enhances the capability of providing a dependable guarantee for success-ful accomplishment of flight missions.Nonetheless,assuring reliability in scene matching encoun-ters significant challenges in areas characterized by repetitive or weak textures.To tackle these challenges,we propose a novel method to assess the reliability of scene matching based on the dis-tinctive characteristics of correlation peaks.The proposed method leverages the fact that the sim-ilarity of the optimal matching result is significantly higher than that of the surrounding area,and three novel indicators(e.g.,relative height,slope of a correlation peak,and ratio of a sub peak to the main peak)are determined to conjointly evaluate the reliability of scene matching.The pro-posed method entails matching a real-time image with a reference image to generate a correlation surface.A correlation peak is then obtained by extracting the portion of the correlation surface exhibiting a significant gradient.Additionally,the matching reliability is determined by considering the relative height,slope,and ratio of the peak collectively.Exhaustive experimental results with two sets of data demonstrate that the proposed method significantly outperforms traditional approaches in terms of precision,recall,and F1-score.These experiments also establish the efficacy of the proposed method in achieving reliable matching in challenging environments characterized by repetitive and weak textures.This enhancement holds the potential to significantly elevate scene-matching-based navigation. 展开更多
关键词 Unmanned aerial vehicle Scene matching navigation Multimodal scene matching Correlation peak Reliabilityanalysis
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Enhanced quasi-three-dimensional transient simulation technique incorporating component volume effects for aero engine
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作者 Yuchen DAI Manxiang SONG +1 位作者 Donghai JIN Xingmin GUI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第12期325-346,共22页
Current transient analysis predominantly relies on zero-dimensional/one-dimensional tools,proficient at capturing aerothermodynamic variations across critical engine stations but insufficient for analyzing the interna... Current transient analysis predominantly relies on zero-dimensional/one-dimensional tools,proficient at capturing aerothermodynamic variations across critical engine stations but insufficient for analyzing the internal flow field evolution during transients.Addressing this gap,the study presents an enhanced quasi-three dimensional(quasi-3D)transient simulation technique that integrates component volume effects,offering a significant leap from the preceding quasi-3D transient simulation method based on quasi-steady assumption.By embedding the component volume effects on density,momentum,and energy within the physical temporal dimension of the Navier-Stokes equations,the refined quasi-3D transient model achieves a closer representation of physical phenomena.Validation against a single-shaft turbofan engine’s experimental data confirms the model’s accuracy.Average errors for key performance indicators,including shaft speed,thrust,mass flow rate,and critical component exit temperature and pressure,remain below 0.41%,5.69%,2.55%,3.18%and 0.67%,respectively.Crucially,the model exposes a discernible temporal lag in the compressor outlet pressure and temperature response due to volume effects—previously unquantified in quasi-3D transient simulations.And further exploration of the meridional flow field emphasizes the consequential role of volumes in transient flow field evolution.Incorporating volume effects within quasi-3D transient simulations enhances engine modeling and is pivotal for precise transient analysis in engine design and optimization. 展开更多
关键词 Engines Transient simulation Quasi-3D modeling Component volume effects Flow field evolution Transient performance analysis
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Event-triggered and consensus-based attitude tracking alignment for discrete-time multiple spacecraft system exploiting interference
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作者 Peiran LI Xin WEN +1 位作者 Haiying LIU Yuping LU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第2期241-255,共15页
This paper presents a discrete-time attitude control strategy with equi-global practical stabilizability for aligning the attitude of multiple spacecraft to a predesigned configuration according to a time-variant refe... This paper presents a discrete-time attitude control strategy with equi-global practical stabilizability for aligning the attitude of multiple spacecraft to a predesigned configuration according to a time-variant reference.By utilizing the interference of the wireless channel,the communication scheme designed in this paper can save communication resources,amount of computation,and energy proportionally to the number of spacecraft.The exact discrete-time model and approximate discrete-time model of the consensus-based spacecraft tracking system are given.Then the framework for the design of an event-triggered control scheme for the exact discrete-time system via its approximate models is developed,which avoids the periodic actuation,and Zeno behavior is proved to be excluded.Furthermore,the control scheme can handle the presence of the unknown fading channel.Finally,simulation results are presented to demonstrate the effectiveness of the control strategy. 展开更多
关键词 Attitude control Cooperative communication Discrete time control systems Multi agent systems SPACECRAFT
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Experimental and modeling study of surface topography generation considering tool-workpiece vibration in high-precision turning 被引量:1
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作者 Xingying ZHOU Henan LIU +4 位作者 Tianyu YU Ruiyang GUO Guangzhou WANG Yazhou SUN Mingjun CHEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第7期194-212,共19页
High-precision turning(HPT)is a main processing method for manufacturing rotary high-precision components,especially for metallic parts.However,the generated vibration between tool tip and workpiece during turning may... High-precision turning(HPT)is a main processing method for manufacturing rotary high-precision components,especially for metallic parts.However,the generated vibration between tool tip and workpiece during turning may seriously deteriorate the surface integrity.Therefore,exploring the effect of vibration on turning surface morphology and quality of copper parts using 3D surface topography regeneration model is crucial for predicting HPT performance.This developed model can update the machined surface topology in real time.In this study,the effects of tool arc radius,feed rate,radial vibration,axial vibration and tangential vibration on the surface topography and surface roughness were explored.The results show that the effect of radial vibration on surface topography is greater than that of axial vibration and tangential vibration.The radial vibration frequency is also critical.When vibration frequency changes,the surface topography profile presents three different types:the standard sinusoidal curve,the sinusoidal curve whose lowfrequency signal envelopes high-frequency signal,and the oscillation curve whose low-frequency signal superimposes high-frequency signal.In addition,HPT experiment was carried out to validate the developed model.The surface roughness obtained in the experiment was Ra=53 nm,while the roughness obtained by the simulation was Ra=46 nm,achieving a prediction accuracy of 86.7%.Received 4 September 2022;revised 3 October 2022;accepted 17 October 2022. 展开更多
关键词 High-precision turning Machining vibration Modeling Surface roughness Surface topography
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Application of immersed boundary method in turbomachines 被引量:2
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作者 Congcong CHEN Yuwei WANG +2 位作者 Zhuo WANG Lin DU Xiaofeng SUN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第5期268-279,共12页
Simulating unsteady turbulent flow in turbomachines is still challenging due to the complexity of blade geometry and relative motion between rotor and stator.This study presents an Immersed Boundary Method(IBM)for hig... Simulating unsteady turbulent flow in turbomachines is still challenging due to the complexity of blade geometry and relative motion between rotor and stator.This study presents an Immersed Boundary Method(IBM)for high-Reynolds turbomachinery internal flows,and shows the advantage of the automatic grid generation techniques and flexible moving boundary treatments.The wall functions are used in the present method to alleviate the wall resolution restriction of turbulence simulation.The Two-Dimensional(2-D)IBM solver,which was previously developed and tested for a low-speed compressor,is further validated for a well-documented Low-Pressure Turbine(LPT)cascade.Both the blade loading and the total pressure losses in the wake are well captured by the present 2-D solver.The complex Three-Dimensional(3-D)effects in turbomachines motivate the further development of an extended 3-D IBM solver by using a curvilinear-coordinate system that facilitates the hub and casing boundary treatment.The good performance of the 3-D solver is demonstrated through comparison with CFX solver solutions for the rotor configuration of Advanced Noise Control Fan(ANCF).Further effects of the grid resolution on capturing the blade wake are discussed.The results indicate that the present 3-D solver is capable of reproducing the evolution of the blade wake with suitable computational grid. 展开更多
关键词 Immersed boundary method TURBOMACHINERY Turbulence simulation Wake prediction Wall function
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Integrated passage design based on extended free-form deformation and adjoint optimization 被引量:1
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作者 Xin LI Tongtong MENG +2 位作者 Weiwei Li Ling ZHOU Lucheng JI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第4期148-164,共17页
Inspired by the three-dimensional design of flow passages in turbomachinery,this study proposes the concept of integrated passage design.The capability of adjoint method for efficient optimization and the flexibility ... Inspired by the three-dimensional design of flow passages in turbomachinery,this study proposes the concept of integrated passage design.The capability of adjoint method for efficient optimization and the flexibility of the parameterization method based on extended free-form defor-mation have been considered to develop a feasible approach to design an integrated passage.This concept was applied to redesign a typical transonic fan,Rotor 67,and the results were analyzed by CFX.It is shown that the passage was adequately adjusted in all three dimensions and reduced the strength of shock wave and wake-induced flow.In particular,the secondary flow was appropriately reorganized and the corner separation was well controlled in the end wall region,leading to signif-icant improvements in adiabatic efficiency and diffusion. 展开更多
关键词 TURBOMACHINERY Aerodynamic Transonic flow Integrated passage design Extended free-form defor-mation Adjoint optimization
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Numerical analysis on combustion characteristics of hybrid rocket motor with star-tube segmented grain 被引量:3
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作者 Chengen LI Zongwei WANG +4 位作者 Jin YANG Jinpeng JIANG Fan GONG Zhu LIU Yu SUN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第12期102-112,共11页
A method of star-tube combined segmented grain is proposed to improve the combustion performance of hybrid rocket motor.The star-tube combined segmented grain consists of a single-port star part and a single-port tube... A method of star-tube combined segmented grain is proposed to improve the combustion performance of hybrid rocket motor.The star-tube combined segmented grain consists of a single-port star part and a single-port tube part.A mid-chamber forms between the fore-grain and the aft-grain for better mixing effect.The single-port feature gives hybrid rocket motor several advantages,such as simple structure,high reliability,and variable combinations.This paper is mainly aimed at studying the combustion characteristics of hybrid rocket motor with star-tube segmented grain through three-dimensional steady simulations.Combustion performance of the motors with different segmented grain combinations,including fore-tube/aft-tube,fore-tube/aftstar,fore-star/aft-star and fore-star/aft-tube,is contrastively analyzed.The motor in this paper adopts polyethylene and 90%hydrogen peroxide as the propellants.Simulations reveal that segmented grain with different-type grain combinations could greatly change the flow field in the second half of the combustion chamber.Transformation of the flow field is beneficial to the mixing between the fuel and the oxidizer,and it could increase the fuel regression rate and the combustion efficiency.The turbulence effect of tube aft-grain is better than that of star aft-grain.Among the four segmented grain combinations,the combination of star fore-grain and tube aft-grain is the preferred method with optimal overall performance.This grain configuration could increase the regression rate of tube aft-grain to surpass that of star aft-grain in other combinations.Besides,hybrid rocket motor with this grain configuration achieves the highest combustion efficiency. 展开更多
关键词 Combustion performance Flow fields Fluid-solid coulping Hybrid rocket motor Star-tube segmented grain
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Flow characteristics of integrated motor-pump assembly with phosphate ester medium for aerospace electro-hydrostatic actuators 被引量:2
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作者 Jiangao ZHAO Jian FU +3 位作者 Yuchen LI Haitao QI Yan WANG Yongling FU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第9期392-407,共16页
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 ... 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 mediums.Our ultimate goal is to pursue better flow characteristics under a wide range of working conditions.In 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 modeling.The experimental investigation of the output characteristics was mainly carried out in a phosphate ester medium environment.Then,the flow characteristics were compared and analyzed with the simulation results.Results 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. 展开更多
关键词 EHA Friction interfaces More electric aircraft Motor-pump Multidisciplinary modeling
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Competing effects of surface catalysis and ablation in hypersonic reentry aerothermodynamic environment 被引量:6
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作者 Zhiliang CUI Jin ZHAO +4 位作者 Guice YAO Jun ZHANG Zhihui LI Zhigong TANG Dongsheng WEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第10期56-66,共11页
Under hypersonic flow conditions, the complicated gas-graphene interactions including surface catalysis and surface ablation would occur concurrently and intervene together with the thermodynamic response induced by s... Under hypersonic flow conditions, the complicated gas-graphene interactions including surface catalysis and surface ablation would occur concurrently and intervene together with the thermodynamic response induced by spacecraft reentry. In this work, the competing effects of surface heterogeneous catalytic recombination and ablation characteristics at elevated temperatures are investigated using the Reactive Molecular Dynamics(RMD) simulation method. A GasSurface Interaction(GSI) model is established to simulate the collisions of hyper-enthalpy atomic oxygen on graphene films in the temperature range of 500–2500 K. A critical temperature Tcaround900 K is identified to distinguish the graphene responses into two parts: at T < T_(c), the heterogeneous surface catalysis dominates, while the surface ablation plays a leading role at T > T_(c). Contradicting to the traditional Arrhenius expression that the recombination coefficient increases with the increase of surface temperature, the value is found to be relatively uniform at T < T_(c) but declines sharply as the surface temperature increases further due to the competing ablation effect. The occurrence of surface ablation decreases the amounts of active sites on the graphene surface for oxygen adsorption, leading to reduced recombination coefficient from both Langmuir-Hinshelwood(L-H) and Eley-Rideal(E-R) mechanisms. It suggests that the traditional Computational Fluid Dynamics(CFD) simulation method, which relies on the Arrhenius-type catalysis model, would result in large discrepancies in predicting aerodynamic heat for carbon-based materials during reentry into strong aerodynamic thermal environment. 展开更多
关键词 Ablation fluid dynamics Gas-solid reaction GRAPHENE Hypersonic reentry Molecular dynamics simulation Recombination effects
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Topology tracking of dynamic UAV wireless networks 被引量:1
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作者 Yehui SONG Guoru DING +2 位作者 Jiachen SUN Jinghua LI Yitao XU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第11期322-335,共14页
Wireless network is the communication foundation that supports the intelligentization of Unmanned Aerial Vehicle(UAV) swarm. The topology of UAV communication network is the key to understanding and analyzing the beha... Wireless network is the communication foundation that supports the intelligentization of Unmanned Aerial Vehicle(UAV) swarm. The topology of UAV communication network is the key to understanding and analyzing the behavior of UAV swarm, thus supporting the further prediction of UAV operations. However, the UAV swarm network topology varies over time due to the high mobility and diversified mission requirements of UAVs. Therefore, it is important but challenging to research dynamic topology inference for tracking the topology changes of the UAV network,especially in non-cooperative manner. In this paper, we study the problem of inferring UAV swarm network topology based on external observations, and propose a dynamic topology inference method. First, we establish a sensing framework for acquiring the communication behavior of the target network over time. Then, we expand the multi-dimensional dynamic Hawkes process to model the communication event sequence in a dynamic wireless network. Finally, combining the sliding time window mechanism, the maximum weighted likelihood estimation is applied to inferring the network topology. Extensive simulation results demonstrate the effectiveness of the proposed method. 展开更多
关键词 Dynamic topology inference Event detection Hawkes process UAV swarm Wireless networks
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SINS/GNSS integrated navigation system based on maximum versoria filter 被引量:7
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作者 Chunhui ZHAO Zhenyu YANG +2 位作者 Xiaoran CHENG Jinwen HU Xiaolei Hou 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第8期168-178,共11页
In the missile-borne Strapdown Inertial Navigation System/Global Navigation Satellite System(SINS/GNSS)integrated navigation system,due to the factors such as the high dynamics,the signal blocking by obstacles,the sig... In the missile-borne Strapdown Inertial Navigation System/Global Navigation Satellite System(SINS/GNSS)integrated navigation system,due to the factors such as the high dynamics,the signal blocking by obstacles,the signal intefereces,etc.,there always exist pulse interferences or measurement information interruptions in the satellite receiver,which make nonstationary measurement process.The traditional Kalman Filter(KF)can tackle the state estimation problem under Gaussian white noise,but its performance will be significantly reduced under nonGaussian noises.In order to deal with the non-Gaussian conditions in the actual missile-borne SINS/GNSS integrated navigation systems,a Maximum Versoria Criterion Extended Kalman Filter(MVC-EKF)algorithm is proposed based on the MVC and the idea of M-estimation,which assigns a smaller weight to the anomalous measurements so as to suppress the influence of anomalous measurements on the state estimation while maintaining a relatively low calculation cost.Finally,the integrated navigation simulation experiments prove the effectiveness and robustness of the proposed algorithm. 展开更多
关键词 Extended Kalman filter Gaussian kernel function Maximum versoria criterion Missile-borne SINS/GNSS integrated systems
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Method for utilizing PIV to investigate high curvature and acceleration boundary layer flows around the compressor blade leading edge
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作者 Baojie LIU Xiaobin XU +1 位作者 Xianjun YU Guangfeng AN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第12期72-88,共17页
Particle Image Velocimetry(PIV)is a well-developed and contactless technique in experimental fluid mechanics,but the strong velocity gradient and streamline curvature near the wall substantially limits its accuracy im... Particle Image Velocimetry(PIV)is a well-developed and contactless technique in experimental fluid mechanics,but the strong velocity gradient and streamline curvature near the wall substantially limits its accuracy improvement.This paper presents a data processing procedure combining conventional PIV and newly developed Mirror Interchange(MI)based Interface-PIV for the measurement of the boundary layer parameter development in the blade leading edge region.The synthetic particle images are used to analyze the measurement errors in the entire procedure.Overall,three types of errors,namely the errors caused by the Window Deformation Iterative Multigrid(WIDIM)algorithm,the discrete data interpolation and integration,and the wall offset uncertainty,comprise the main measurement error.Specifically,the errors due to the discrete data interpolation and integration and the WIDIM algorithm comprise the mean bias,which can be corrected through the error analysis method proposed in the present work.Meanwhile,the errors due to the WIDIM algorithm and the wall offset uncertainty contribute to the measurement uncertainty.Computational fluid dynamics-based synthetic particle flows were generated to verify the newly developed PIV data processing procedure and the corresponding error analysis method.Results showed that the data processing method could improve the accuracy of PIV measurements for boundary layer flows with high curvature and acceleration and even with significant flow separation bubbles.Finally,the data processing method is also applied in a PIV experiment to investigate the boundary layer flows around a compressor blade leading edge,and several credible boundary flow parameters were obtained. 展开更多
关键词 Boundary layer measurement Compressor blade leading edge Mirror interchange method Particle image velocimetry Planar cascade experiment
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Design and experimental research of a sub-Newton N_(2)O monopropellant thruster with inner-heater 被引量:1
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作者 Kaiyang LI Jie FANG +2 位作者 Wei SUN Bing SUN Guobiao CAI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第5期309-318,共10页
Nitrous oxide(N_(2)O)is a green propellant with excellent application prospects.A subNewton N_(2)O monopropellant thruster with inner-heater and a N_(2)O self-pressurization stable supply system with regenerative heat... Nitrous oxide(N_(2)O)is a green propellant with excellent application prospects.A subNewton N_(2)O monopropellant thruster with inner-heater and a N_(2)O self-pressurization stable supply system with regenerative heat compensation are designed in this paper.The experimental research of the thruster is described,including measurements of preheating power,activation temperature,vacuum thrust,specific impulse,life-span and pulsed operation performance.By inserting the heater into the catalyst-bed,preheating efficiency of the heater is significantly improved compared to the thruster with outer-heater.Thus,the preheating power demand of the thruster is successfully reduced to around 10 W.The mean vacuum thrust of 322 mN is attained and the corresponding specific impulse reaches 162s at the mass flow rate of 0.2 g/s.Successful activation temperature of 523 K is achieved,and the activation performance of the thruster is affected by the loading factor.A long term hot-firing test longer than 12000 s is attained.The pulsed operation performance of the inner-preheating thruster is also studied by measuring chamber pressure.Impulses with different magnitudes are produced by adjusting the opening duration of the control valve.A minimum impulse of 81 mN·s is attained.Finally,the performance of the thruster is evaluated by comparison with other thrusters of the same type.The results indicate that the proposed thruster with inner-heater is superior in terms of preheating power,activation temperature and specific impulse performance. 展开更多
关键词 Green propellant Monopropellant thruster Nitrous oxide Regenerative heat compensation Self-pressurization
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Effects of swirler position on flame response and combustion instabilities 被引量:3
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作者 Liangliang XU Jianyi ZHENG +2 位作者 Guoqing WANG Lei LI Fei QI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第3期345-355,共11页
This study is concerned with the experimental and theoretical investigation of the combustion instabilities in a premixed swirl combustor.It is focused on the effects of the swirl mixing distance on the intrinsic ther... This study is concerned with the experimental and theoretical investigation of the combustion instabilities in a premixed swirl combustor.It is focused on the effects of the swirl mixing distance on the intrinsic thermoacoustic mode.The swirler as an origin of the swirling flow is also the source of the flow disturbance,which has effects on the flame response.The location of the swirler is varied in the experiment to study the effect on combustion instabilities and flame transfer functions.A low order model is built to analyze the thermoacoustic instabilities of the combustion system.The experimental results show that the ITA switches from an unstable state to a stable state as the swirl mixing distance changes with an increment of 15 mm;while the instability of the quarter-wave mode is not varied.The measured Flame Transfer Functions(FTFs)show that the gain curves of the frequency-dependent FTFs seem to be stretched or compressed with the modulation of the swirler position,which has effects on frequencies and instabilities of thermoacoustic modes.With the low order model,the effects of flame response on combustion instabilities are analyzed and the flame dominant nature of the ITA mode is confirmed. 展开更多
关键词 Intrinsic thermoacoustic instability Lean premixed combustion Mode switch Swirl flame Swirler position
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Passage shock wave/boundary layer interaction control for transonic compressors using bumps 被引量:2
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作者 Yongzhen LIU Wei ZHAO +2 位作者 Qingjun ZHAO Qiang ZHOU Jianzhong XU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第2期82-97,共16页
Flow separation due to shock wave/boundary layer interaction is dominated in blade passage with supersonic relative incoming flow,which always accompanies aerodynamic performance penalties.A loss reduction method for ... Flow separation due to shock wave/boundary layer interaction is dominated in blade passage with supersonic relative incoming flow,which always accompanies aerodynamic performance penalties.A loss reduction method for smearing the passage shock foot via Shock Control Bump(SCB)located on transonic compressor rotor blade suction side is implemented to shrink the region of boundary layer separation.The curved windward section of SCB with constant adverse pressure gradient is constructed ahead of passage shock-impingement point at design rotor speed of Rotor 37 to get the improved model.Numerical investigations on both two models have been conducted employing Reynolds-Averaged Navier-Stokes(RANS)method to reveal flow physics of SCB.Comparisons and analyses on simulation results have also been carried out,showing that passage shock foot of baseline is replaced with a family of compression waves and a weaker shock foot for moderate adverse pressure gradient as well as suppression of boundary layer separations and secondary flow of low-momentum fluid within boundary layer.It is found that adiabatic efficiency and total pressure ratio of improved blade exceeds those of baseline at 95%-100%design rotor speed,and then slightly worsens with decrease of rotatory speed till both equal below 60%rated speed.The investigated conclusion implies a potential promise for future practical applications of SCB in both transonic and supersonic compressors. 展开更多
关键词 Flow separation Passage shock Shock Control Bump(SCB) Shock wave/boundary layer interaction Transonic compressors
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