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APPLICATION OF HYBRID AERO-ENGINE MODEL FOR INTEGRATED FLIGHT/PROPULSION OPTIMAL CONTROL 认领 引用 被引量：5
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作者 王健康 张海波 +1 位作者 孙健国 李永进 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第1期16-24,共9页
The real-time capability of integrated flight/propulsion optimal control （IFPOC） is studied. An appli- cation is proposed for IFPOC by combining the onboard hybrid aero-engine model with sequential quadratic pro- gr... The real-time capability of integrated flight/propulsion optimal control （IFPOC） is studied. An appli- cation is proposed for IFPOC by combining the onboard hybrid aero-engine model with sequential quadratic pro- gramming （SQP）. Firstly, a steady-state hybrid aero-engine model is designed in the whole flight envelope with a dramatic enhancement of real-time capability. Secondly, the aero-engine performance seeking control including the maximum thrust mode and the minimum fuel-consumption mode is performed by SQP. Finally, digital simu- lations for cruise and accelerating flight are carried out. Results show that the proposed method improves real- time capability considerably with satisfactory effectiveness of optimization. 展开更多
关键词 integrated flight/propulsion optimal control aero-engine hybrid model performance seeking con- trol sequential quadratic programming
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THE EIGENVALUE SENSITIVITY ANALYSIS AND DESIGN FOR INTEGRATED FLIGHT/PROPULSION CONTROL SYSTEM 认领 引用
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作者 Shen Gongzhang, Chen Zongji and Peng KemaoBeijing University of Aeronautics and Astronautics 《Chinese Journal of Aeronautics》 EI CAS 1990年第4期277-284,共8页
In this paper, sensitivity approaches are taken to analyze and design an integrated flight propulsion control system where the interaction between subsystems direitly affects the stability property and handling perfor... In this paper, sensitivity approaches are taken to analyze and design an integrated flight propulsion control system where the interaction between subsystems direitly affects the stability property and handling performances of the aircraft. The eigenvalue sen sitivity approach is employed to study the effect of coupling parameters on system stability and gain sensitivity approach is used to direct the reduced states feedback suboptimal control system design. Simulation results show that the integrated flight propulsion control system designed by sensitivity approaches is of good performance. 展开更多
关键词 THE EIGENVALUE SENSITIVITY ANALYSIS AND DESIGN FOR INTEGRATED FLIGHT/PROPULSION CONTROL SYSTEM Simulation
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Liquid Metal-Driven Pulsed Jet Propulsion in a Squid-Inspired Robotic Fish 认领 引用
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作者 Gang Ma Xiao Pan +3 位作者 Huarui Rong Du-An Ge Shuai Dong Shiwu Zhang 《Journal of Bionic Engineering》 SCIE EI CSCD 2026年第2期652-662,共11页
Pulsed jet propulsion,a highly efficient locomotion strategy prevalent among marine organisms,offers significant potential for bio-inspired underwater robotics.Drawing inspiration from the jet propulsion mechanism of ... Pulsed jet propulsion,a highly efficient locomotion strategy prevalent among marine organisms,offers significant potential for bio-inspired underwater robotics.Drawing inspiration from the jet propulsion mechanism of squids,this study presents the design and implementation of a soft biomimetic robotic fish driven by a liquid metal-based electromagnetic actuator.The robot employs a novel driving strategy,wherein Lorentz forces generated through the interaction between an embedded permanent magnet and an energized liquid metal coil induce periodic contraction and relaxation of the flexible main chamber,enabling efficient pulsed jet propulsion.Through comprehensive analysis of actuator dynamics and system-level structural and control parameters,the robotic fish achieves a straight-line swimming speed of 1.71 BL/s(body lengths per second),corresponding to 8.9 cm/s,in underwater environments.To enhance maneuverability,a linear chamber parallel inclined nozzle design is adopted,achieving precise directional control with a maximum turning rate of 47.4 deg/s and a minimum turning radius of 0.4 BL.Furthermore,miniaturized power and control systems are successfully integrated inside the body,enabling fully untethered autonomous swimming of the robot,greatly enhancing system practicality.Experimental results demonstrate that the proposed robotic fish combines compact structure,rapid response,versatile control,and excellent locomotion performance,highlighting its strong application potential in marine exploration,underwater surveillance,and environmental monitoring. 展开更多
关键词 squid-inspired robotic fish pulsed jet propulsion liquid metal electromagnetic actuators high-speed propulsion
Catalase-powered Micro/Nanorobots:Propulsion Mechanisms and Biomedical,Environmental,and Industrial Applications 认领 引用
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作者 Jitendra Gupta Abdulla Ahmed Al-dulaimi +7 位作者 Mudher Kadhem Irfan Ahmad S.Renuka Jyothi Rajashree Panigrahi Indu Singh Surbhi Singh Nafaa Farhan Muften Yasser Fakri Mustafa 《Journal of Bionic Engineering》 SCIE EI CSCD 2026年第1期34-54,共21页
Microanorobots represent a groundbreaking advancement in nanotechnology,with applications spanning medicine,envi-ronmental remediation,and industrial processes.A major challenge in their development is achieving effic... Microanorobots represent a groundbreaking advancement in nanotechnology,with applications spanning medicine,envi-ronmental remediation,and industrial processes.A major challenge in their development is achieving efficient and bio-compatible propulsion.Enzyme-driven propulsion,particularly using catalase,offers a promising solution due to its ability to decompose hydrogen peroxide(H2O2)into water and oxygen,generating thrust for autonomous movement.Compared to metal-based catalysts,catalase-powered systems exhibit superior biocompatibility and lower toxicity,making them ideal for biomedical applications.This review explores the role of catalase in microanorobot propulsion,highlighting self-propulsion mechanisms,different nanorobot types,and their applications in drug delivery,infection treatment,cancer therapy,and biosensing.Additionally,recent advancements in biodegradable enzyme-powered nanorobots and their poten-tial in overcoming biological barriers are discussed.With further research,catalase-driven nanorobots could revolutionize targeted therapy and diagnostic techniques,paving the way for innovative solutions in nanomedicine. 展开更多
关键词 Catalase-powered nanorobots Enzyme-driven propulsion Drug delivery system Targeted therapy Biomedical nanotechnology
Identification of underwater suction vortex at the inlet of a ship's waterjet propulsion pump device via volumetric three-component velocimetry(V3V) 认领 引用
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作者 Weixuan Jiao Xuanwen Jia +1 位作者 Li Cheng Bowen Zhang 《Defence Technology（防务技术）》 SCIE EI CAS CSCD 2026年第6期254-272,共19页
Waterjet propulsion systems,as the predominant form of propulsion for high-performance vessels,are widely employed in military ships across various navies.However,when operating in shallow water conditions,underwater ... Waterjet propulsion systems,as the predominant form of propulsion for high-performance vessels,are widely employed in military ships across various navies.However,when operating in shallow water conditions,underwater suction vortices(USVs)are prone to form near the pump inlet.These vortices can markedly degrade the hydraulic performance of the waterjet propulsion system by reducing efficiency and potentially inducing cavitation and associated vibrations.The formation and evolution of USVs occur underwater,rendering them highly elusive and difficult to detect or measure accurately.As a result,investigating the underlying mechanisms of USV generation and developing effective control strategies remain substantial challenges in the field.To achieve precise identification and capture of USVs,volumetric three component velocimetry technology was employed to conduct high-precision analyses of the three-dimensional spatiotemporal evolution signals and vortex dynamic characteristics of USVs throughout their entire lifecycle.The findings demonstrate that the typical evolution of USVs can be categorized into five stages:precursor,inception,development,weakening,and dissipation.During their evolution,both velocity and vorticity within USVs initially increase before subsequently decreasing.Notably,the velocity distribution within the vortex core conforms to the Rankine composite vortex model.The adverse pressure gradient at the riverbed,combined with the suction flow of the pump,directly facilitates USV generation.These findings provide a critical foundation for USV identification,offering a valuable method for flow-field testing in vortex and other fault identification,while overcoming the limitations of conventional point sensors in complex flow diagnostics. 展开更多
关键词 Waterjet propulsion Vortex dynamics Spatiotemporal evolution Underwater suction vortex Volumetric three-component velocimetry Model test
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Dynamic characteristics and sensitivity of water hammer problems in liquid propulsion system using lattice Boltzmann method with entropy limiter 认领 引用 被引量：1
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作者 Yuqi WEI Xianggeng WEI +4 位作者 Guoqiang HE Xiao ZHAO Jinying YE Xueren WANG Hongyu CHEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第1期18-34,共17页
The water hammer problem is an important issue in the dynamics of liquid propulsion system.This paper aims to use the Lattice Boltzmann Method(LBM)with entropy limiter to study the water hammer problems in propellant ... The water hammer problem is an important issue in the dynamics of liquid propulsion system.This paper aims to use the Lattice Boltzmann Method(LBM)with entropy limiter to study the water hammer problems in propellant feedlines.The dynamic characteristics of valve-closing water hammer and filling water hammer are investigated by this method,and the sensitivity of filling water hammer is analyzed with a single factor sensitivity analysis with 8 factors and 9 levels and a multi-factor sensitivity analysis with L27(313)orthogonal experiment based on range method.It is found that the solving result of LBM with entropy limiter is basically in good agreement with finite volume method,and using the entropy limiter can eliminate numerical oscillations when solving valve-closing water hammer problems and solve the numerical"blow up"when solving filling water hammer problems.It can be seen that the dynamic characteristics of valve-closing water hammer are relatively simple,while there are many factors that affect the filling water hammer and the degree of these effects varies.The effects on the maximum water hammer pressure are relatively uniform,but those on the water hammer response time vary greatly through the skewness analysis. 展开更多
关键词 Dynamic analysis Lattice Boltzmann method Liquid propulsion system Propellant transfer Sensitivity analysis Water hammer
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Vibration reduction of propulsion shaft system by optimized bearing parameters 认领 引用
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作者 LIU Jian-yu GENG Xiao-ming +2 位作者 LI Xin-bin LIU Jing XU Ya-jun 《Journal of Central South University》 SCIE EI CAS CSCD 2026年第6期2808-2828,共21页
The vibrations of the propulsion shaft systems have a critical impact on the performance and noise control of underwater vehicles.Bearings are essential for the system's dynamic performance as the support componen... The vibrations of the propulsion shaft systems have a critical impact on the performance and noise control of underwater vehicles.Bearings are essential for the system's dynamic performance as the support components.Existing studies have primarily focused on the impacts of the individual bearing parameters on system vibrations,while the effects of bearing designation,clearance,tolerance,and bearing arrangement on the multi-bearing propulsion shaft system dynamics remain unclear.There is a lack of optimized design for multi-bearing parameters in propulsion shaft systems.A comprehensive dynamic model of the multi-bearing propulsion shaft system is developed in this study,which includes key components such as support bearings and the propeller.The effects of different bearings at different positions and bearing parameters on key vibration indicators(such as acceleration and displacement)are revealed through dynamic simulations.Based on the simulation results,a vibration optimization model for a multi-bearing propulsion shaft system is proposed,which can select effective bearing parameters.The optimal bearing parameters of the propulsion shaft system can be obtained through the optimization model.The findings not only provide quantitative criteria for low-vibration design of underwater propulsion systems,but also provide a theoretical reference for modeling and vibration control of complex multi-support rotating machinery. 展开更多
关键词 vibration reduction propulsion shaft systems bearing parameter optimization dynamic modeling
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Fiber optic sensing technology for space propulsion system applications 认领 引用
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作者 WANG Siying HU Jun +3 位作者 CHEN Jun FU Xinju WANG Xudong LIU Xuhui 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2026年第1期141-150,共10页
A comprehensive review of the application status,key technical challenges,and future trends of fiber optic sensing technology applied in space propulsion systems is presented,exploring the feasibility and advantages o... A comprehensive review of the application status,key technical challenges,and future trends of fiber optic sensing technology applied in space propulsion systems is presented,exploring the feasibility and advantages of replacing traditional electronic sensors with fiber optic sensors in extreme space environments.The fundamental principles of fiber optic sensing technology are analyzed,especially focusing on the mathematical models and operational mechanisms of fiber Bragg grating(FBG)and Fabry-Pérot(F-P)cavity sensors.Furthermore,the latest experimental research and technical solutions are summarized in three typical application scenarios:dynamic strain measurement in cryogenic pipelines,design of intelligent propellant tanks,and temperature distribution monitoring of thermal protection materials in electric propulsion systems.Results demonstrate that packaged FBG sensors can effectively suppress spectral distortion at liquid nitrogen temperatures,enabling accurate strain measurement in small-diameter pipelines;fiber optic sensors embedded in carbon fiber composites can provide real-time structural health and leakage monitoring;and distributed optical frequency domain reflectometry(OFDR)systems can achieve millimeter-level spatial resolution for temperature field monitoring.The discussion identifies remaining technical bottlenecks such as environmental adaptability,packaging techniques,cross-sensitivity,and long-term stability.Future development should focus on integration with smart materials,quantum sensing,on-orbit maintenance,and data-driven decision-making to evolve fiber optic sensing from merely replacing traditional sensors towards enabling intelligent structural systems. 展开更多
关键词 fiber optic sensing technology space propulsion systems structural health monitoring embedded fiber optic sensors space applications propellant tanks
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Green Marine Fuels and Wind-Assisted Propulsion in Shipping:Market Trajectories and a Portugal–China Cooperation Agenda 认领 引用
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作者 Ruben Eiras 《China Oil & Gas》 CAS 2026年第2期4-10,共7页
The energy transition in shipping is simultaneously happening everywhere and nowhere: everywhere in boardrooms, regulation, and newbuild specifications;nowhere in the global fuel statistics-at least not yet. A recent ... The energy transition in shipping is simultaneously happening everywhere and nowhere: everywhere in boardrooms, regulation, and newbuild specifications;nowhere in the global fuel statistics-at least not yet. A recent IEA Bioenergy assessment puts this paradox in numbers: biofuel blends bunkered for ships were only around 0.5% of global marine fuel volumes in 2024(measured in tons of biofuels versus fossil fuels), despite biofuel deliveries being reported on all continents.1 展开更多
关键词 fossil fuels despite wind assisted propulsion green marine fuels marine fuel shipping iea bioenergy assessment energy transition global fuel
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Aero-propulsion analysis of distributed ducted-fan propulsion based on lifting-line driven body-force model 认领 引用 被引量：2
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作者 Hanru LIU Xingyu ZHAO +2 位作者 Fang ZHOU Yuyao FENG Yangang WANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2025年第2期60-74,共15页
As the environmental problems become increasingly serious,distributed electrical propulsion systems with higher aerodynamic efficiency and lower pollution emission have received extensive attention in recent years.The... As the environmental problems become increasingly serious,distributed electrical propulsion systems with higher aerodynamic efficiency and lower pollution emission have received extensive attention in recent years.The distributed electrical propulsion usually employs the new aero-propulsion integrated configuration.A simulation strategy for internal and external flow coupling based on the combination of lifting line theory and body force method is proposed.The lifting line theory and body force method as source term are embedded into the Navier-Stokes formulation.The lift and drag characteristics of the aero-propulsion coupling configuration are simulated.The results indicate that the coupling configuration has the most obvious lift augmentation at 12°angle of attack,which can provide an 11.11%increase in lift for the airfoil.At 0°angle of attack,the pressure difference on the lip parts provides the thrust component,which results in a lower drag coefficient.Additionally,the failure impact of a ducted fan at the middle or edge on aerodynamics is investigated.For the two failure conditions,the lift of the coupling configuration is decreased significantly by 27.85%and 26.14%respectively,and the lip thrust is decreased by 70.74%and 56.48%respectively. 展开更多
关键词 Ducted fan Distributed electrical propulsion Lifting line theory Body force method Aero-propulsion integrated configuration
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Research on the Ice Resistance and Propulsion Performance of Polar Ships via the CFD-DEM Coupling Method 认领 引用
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作者 ZHENG Si-jie SONG Bo-yang +5 位作者 ZHOU Li HUANG Qiao-gao XIE Chang LI Han HE Guang-wei LING Hong-jie 《China Ocean Engineering》 SCIE EI CSCD 2025年第2期232-243,共12页
Polar marine equipment plays an important role in Arctic engineering,especially in the development of polar ships and ice-class propellers.When polar ships navigate in brash ice channels,the brash ice not only increas... Polar marine equipment plays an important role in Arctic engineering,especially in the development of polar ships and ice-class propellers.When polar ships navigate in brash ice channels,the brash ice not only increases resistance but also has adverse effects on their propulsion performance.On the basis of coupled computational fluid dynamics(CFD)and the discrete element method(DEM),this paper aims to numerically investigate the resistance and propulsion performance of a polar in a brash ice channel while considering the rotation status of the propeller by both experimental and numerical methods.Both ship resistance and ice motion under Froude numbers of 0.0557,0.0696,0.0836,0.975,and 0.1114 are studied when the propeller does not rotate.The influences of the rotating propeller on the ice brash resistance and flow are discussed.The thrust due to the propeller and ice resistance in the equilibrium state are also predicted.The errors between the thrust and total resistance are approximately 1.0%,and the maximum error between the simulated and predicted total resistance is 3.7%,which validates the CFD-DEM coupling method quite well.This work could provide a theoretical basis for the initial design of polar ships with low ice class notation and assist in planning navigation for merchant polar ships in brash ice fields. 展开更多
关键词 polar ships propeller CFD-DEM ice resistance propulsion performance
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Aero-propulsive coupling performance and design of distributed propulsion wing 认领 引用
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作者 Kelei WANG Zhou ZHOU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2025年第4期127-141,共15页
The Distributed Propulsion Wing(DPW)presents prominent advantages in terms of energy conservation during flight,but the intense integration of propulsive internal flow with aerodynamic external flow brings significant... The Distributed Propulsion Wing(DPW)presents prominent advantages in terms of energy conservation during flight,but the intense integration of propulsive internal flow with aerodynamic external flow brings significant design challenges.To tackle this issue,this paper undertakes a comprehensive investigation of the aero-propulsive coupling performance of the DPW under both hovering and cruising conditions,and subsequently proposes a multi-level collaboration optimization design method based on the decomposition principle.Specifically,the complex 3D surfaces of DPW are systematically dissociated into simple 2D curves with inherent relationships for design.The decomposition is achieved based on the analysis results of the aero-propulsive coupling characteristics.And a DPW design case is conducted and subsequently analyzed in order to further validate the effectiveness and feasibility of the proposed design method.It is shown that a 115.75%drag reduction of DPW can be achieved at cruise under a specified thrust level.Furthermore,the DPW exhibits inherent characteristics of consistent lift-to-drag ratio with the thrust-drag balance constraint,regardless of variations in incoming flow velocity or total thrust. 展开更多
关键词 Distributed propulsion wing Aero-propulsive coupling performance Multi-level collaboration optimization design method Decomposition principle Thrust-drag balance
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Thrust-vectoring schemes for electric propulsion systems:A review 认领 引用 被引量：3
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作者 Andrei SHUMEIKO Victor TELEKH Sergei RYZHKOV 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2025年第6期179-203,共25页
Thrust-vectoring capability has become a critical feature for propulsion systems as space missions move from static to dynamic.Thrust-vectoring is a well-developed area of rocket engine science.For electric propulsion... Thrust-vectoring capability has become a critical feature for propulsion systems as space missions move from static to dynamic.Thrust-vectoring is a well-developed area of rocket engine science.For electric propulsion,however,it is an evolving field that has taken a new leap forward in recent years.A review and analysis of thrust-vectoring schemes for electric propulsion systems have been conducted.The scope of this review includes thrust-vectoring schemes that can be implemented for electrostatic,electromagnetic,and beam-driven thrusters.A classification of electric propulsion schemes that provide thrust-vectoring capability is developed.More attention is given to schemes implemented in laboratory prototypes and flight models.The final part is devoted to a discussion on the suitability of different electric propulsion systems with thrust-vectoring capability for modern space mission operations.The thrust-vectoring capability of electric propulsion is necessary for inner and outer space satellites,which are at a disadvantage with conventional unidirectional propulsion systems due to their limited maneuverability. 展开更多
关键词 Electric propulsion Spacecraft propulsion Plasma sources Flight control systems Thrust vectoring Thrust vector control
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Smart Assessment of Flight Quality for Trajectory Planning in Internet of Flying Things 认领 引用
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作者 Weiping Zeng Xiangping Bryce Zhai +3 位作者 Cheng Sun Liusha Jiang Yicong Du Xuefeng Yan 《Computers, Materials & Continua》 SCIE EI 2026年第2期653-667,共15页
With the expanding applications of unmanned aerial vehicles(UAVs),precise flight evaluation has emerged as a critical enabler for efficient path planning,directly impacting operational performance and safety.Tradition... With the expanding applications of unmanned aerial vehicles(UAVs),precise flight evaluation has emerged as a critical enabler for efficient path planning,directly impacting operational performance and safety.Traditional path planning algorithms typically combine Dubins curves with local optimization to minimize trajectory length under 3D spatial constraints.However,these methods often overlook the correlation between pilot control quality and UAV flight dynamics,limiting their adaptability in complex scenarios.In this paper,we propose an intelligent flight evaluation model specifically designed to enhancemulti-waypoint trajectory optimization algorithms.Our model leverages a decision tree to integrate attitude parameters and trajectory matching metrics,establishing a quantitative link between pilot control quality and UAV flight states.Experimental results demonstrate that the proposed model not only accurately assesses pilot performance across diverse skill levels but also improves the optimality of generated trajectories.When integrated with our path planning algorithm,it efficiently produces optimal trajectories while strictly adhering to UAV flight constraints.This integrated framework highlights significant potential for real-time UAV training,performance assessment,and adaptive mission planning applications. 展开更多
关键词 UAV trajectory planning flight quality assessment decision tree
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Recent Development of Aircraft Electric Propulsion System:A Technical Review 认领 引用 被引量：2
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作者 Wei Chen Yexin Yan +2 位作者 Yang Qi Ming Huang Weilin Li 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2025年第1期115-130,共16页
The technology of electric propulsion aircraft(EPA)represents an important direction and an advanced stage in the development of aviation electrification.It is a key pathway for green development in aviation industry ... The technology of electric propulsion aircraft(EPA)represents an important direction and an advanced stage in the development of aviation electrification.It is a key pathway for green development in aviation industry and can significantly enhance the energy efficiency of aircraft propulsion system.Electric motor is the most critical electromechanical energy conversion component in an aircraft electric propulsion system(EPS).High-performance electric motors,power electronic converters and EPS control form the foundation of the EPA.This paper provides an overview of the characteristics of electric motors for EPA,analyzes the inverter topologies of EPSs,and reviews ongoing EPA projects.The article highlights the latest advancements in three types of motors:superconducting motors(SCMs),permanent magnet synchronous motors(PMSMs),and induction motors(IMs).It summarizes the control system architectures of current EPA initiatives and,building on this foundation,proposes future research directions for EPSs.These include cutting-edge areas such as high-performance motors and advanced manufacturing technologies,Ga N-or Si C-based inverter integration and innovation,electric propulsion control systems,and optimization of wiring systems. 展开更多
关键词 Electric propulsion aircraft Inverter topologies Electric motor systems Superconducting motors Distributed electric propulsion
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Learning minimum-time flight control for fixed-wing UAVs in three-dimensional space with high-fidelity 6-DOF dynamics 认领 引用
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作者 Guanzheng Wang Xiangke Wang +2 位作者 Xiaoxin Li Zhihong Liu Zhiqiang Miao 《Journal of Automation and Intelligence》 EI CSCD 2026年第2期126-138,共13页
Minimizing flight time while ensuring stability and efficiency presents a significant challenge in UAV control.This paper introduces velocity-level and actuator-level control approaches for addressing the minimum-time... Minimizing flight time while ensuring stability and efficiency presents a significant challenge in UAV control.This paper introduces velocity-level and actuator-level control approaches for addressing the minimum-time flight problem of fixed-wing UAVs,utilizing a six degrees of freedom(6-DOF)high-fidelity dynamic model and reinforcement learning.We evaluate four state-of-the-art reinforcement learning algorithms through extensive simulations and compare their performance against traditional methods.The results demonstrate that the proposed velocity-level and actuator-level control methods,based on Proximal Policy Optimization(PPO),achieve a substantial improvement in flight efficiency while maintaining strong generalization and stability.Specifically,the PPO-based actuator-level controller fully leverages the UAV’s maneuverability,resulting in a 27.6%reduction in average flight time compared to traditional controllers.The code is available as open source at http://gffzz615be315f87e4109sqnfnk9bwbf696knw.ffgz.tsg.suse.edu.cn/OpenFlight. 展开更多
关键词 Fixed-wing UAV Reinforcement learning(RL) Minimum-time flight Velocity-level control(VLC) Actuator-level control(ALC) High-fidelity dynamics
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Multi-strategy improved sand cat swarm optimization based on somersault pursuit and adaptive Lévy flight 认领 引用
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作者 Wu Jin Xiong Hao +1 位作者 Luo Wenxuan Hao Chengbin 《High Technology Letters》 EI CAS 2026年第1期30-38,共9页
To address the limitations of the sand cat swarm optimization(SCSO) algorithm which are slow convergence and low accuracy in complex problems,this study proposes an improved SCSO(ISCSO) algorithm that integrates multi... To address the limitations of the sand cat swarm optimization(SCSO) algorithm which are slow convergence and low accuracy in complex problems,this study proposes an improved SCSO(ISCSO) algorithm that integrates multiple enhancement strategies.Firstly,Kent chaotic mapping initializes the population for uniform distribution.Secondly,somersault foraging strategy is introduced during the search and attack phases,allowing the algorithm to escape local optima by intercepting evasive prey.Simultaneously,an adaptive Lévy flight strategy is incorporated into the attack phase to bolster global exploration.Finally,the vertical and horizontal crossover strategy is implemented to enhance population diversity.The performance of the proposed algorithm is evaluated using 16 benchmark test functions.The experimental results demonstrate that ISCSO significantly outperforms the original SCSO and shows notable advantages over other metaheuristic algorithms.Furthermore,application to a pressure vessel design problem verifies ISCSO's effectiveness in solving practical engineering optimization challenges. 展开更多
关键词 sand cat swarm optimization Kent chaotic mapping somersault pursuit adaptive Lévy flight vertical and horizontal crossover
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Method to Determine the Propulsion Characteristics of a Ship Moving in Ice 认领 引用 被引量：1
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作者 Kirill Sazonov Grigorii Kanevskii +1 位作者 Alexandr Klubnichkin Aleksei Dobrodeev 《哈尔滨工程大学学报（英文版）》 CSCD 2025年第3期532-541,共10页
In designing modern vessels, calculating the propulsion performance of ships in ice is important, including propeller effective thrust, number of revolutions, consumed power, and ship speed. Such calculations allow fo... In designing modern vessels, calculating the propulsion performance of ships in ice is important, including propeller effective thrust, number of revolutions, consumed power, and ship speed. Such calculations allow for more accurate prediction of the ice performance of a designed ship and provide inputs for designers of ship power and automation systems. Preliminary calculations of ship propulsion and thrust characteristics in ice can enable predictions of full-scale ice resistance without measuring the propeller thrust during sea trials. Measuring propeller revolutions,ship speed, and the power delivered to propellers could be sufficient to determine the propeller thrust of the vessel. At present, significant difficulties arise in determining the thrust of icebreakers and ice-class ships in ice conditions. These challenges are related to the fact that the traditional system of propeller/hull interaction coefficients does not function correctly in ice conditions. The wake fraction becomes negative and tends to minus infinity starting from a certain value of the propeller advance coefficient. This issue prevents accurate determination of the performance characteristics, thrust, and rotational speed of the propulsors. In this study, an alternative system of propeller/hull interaction coefficients for ice is proposed. It enables the calculation of all propulsion parameters in ice based on standard hydrodynamic tests with selfpropulsion models. An experimental method is developed to determine alternative propeller/hull interaction coefficients. A prediction method is suggested to determine propulsion performance in ice based on the alternative interaction coefficient system. A case study applying the propulsion prediction method for ice conditions is provided. This study also discusses the following issues of ship operation in ice: the scale effect of icebreaker propellers and the prospects for introducing an ice interaction coefficient. 展开更多
关键词 Icebreaker Model experiment Interaction coefficients Propeller Calculation Off-design mode Propulsion characteristics Ship moving in ice
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HIERARCHICAL APPROACH AND ITS APPLICATION TO INTEGRATED FLIGHT/PROPULSION CONTROL SYSTEM 认领 引用 被引量：3
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作者 Roan Hongning Shi Zhongke 《Chinese Journal of Aeronautics》 CAS 1996年第4期284-288,共5页
A new model and design method for integrated flight/propulsion control system are presented. To avoid solving higher order Riccati equations, a hierarchical optimization method is developed based on structure perturba... A new model and design method for integrated flight/propulsion control system are presented. To avoid solving higher order Riccati equations, a hierarchical optimization method is developed based on structure perturbation. In the new method, designing of a linear (luadrate regulator (LQR) is divided into two steps: (1 ) computingfeedback gain matrix of individual subsystem, while the association among these subsystems is omittd, and (2) according to the optimization method of LoR, computing thecompensation gain matrix for each subsystem using input perturbation approach. Simulation and application show that not only the results of the new method is as good as that ofan ordinary LQR, but also the efficiency is much higher than that of LQR. 展开更多
关键词 flight control propulsion control perturbation
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Reconstruction of internal flow field in waterjet propulsion pump based on EnKF data assimilation 认领 引用
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作者 Yuyao Zhang Jun Wang +3 位作者 Hualun Zhu Hao Geng Chuangxin He Yingzheng Liu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2025年第8期89-107,共19页
To accurately predict the three-dimensional flow characteristics of the flow field inside a waterjet propulsion pump,data assimilation(DA)method based on unsteady ensemble Kalman filter(EnKF)is used for the reconstruc... To accurately predict the three-dimensional flow characteristics of the flow field inside a waterjet propulsion pump,data assimilation(DA)method based on unsteady ensemble Kalman filter(EnKF)is used for the reconstruction of the flow field of a pump at different flow rates Q/Qopt=0.85,1,1.15,where Qoptis optimal flow rate at the design point.As a compensation to the spatial limitation of planar particle image velocimetry(PIV)measurements,dynamic delayed detached-eddy simulation(DDES)results validated by the PIV data is used to provide the observational data at the optimized probe locations.In DA procedure,the shear stress transport(SST)model constants are optimized by the EnKF approach.The model constants are subsequently rescaled and fitted to form a variation with the flow rate,which is extended to the prediction of the flow field with other flow rates in the vicinity of the design condition.The results show that the SST model with recalibrated constants has improved the prediction of the internal flow field in the waterjet propulsion pump,especially the separation flow in the diffuser section.The modified model constants mainly reduce the eddy viscosity and significantly improve the fluctuation characteristics in the flow field.This study provides a reference for the fast and accurate prediction of the flow field information in the waterjet propulsion pump. 展开更多
关键词 Waterjet propulsion pump Data assimilation Ensemble Kalman filter DDES
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