Evaluating Unmanned Aerial Vehicle(UAV)systems within a System-of-Systems(SoS)environment helps clarify their contribution to the overall combat capability and supports effectiveness-oriented system optimization.When ...Evaluating Unmanned Aerial Vehicle(UAV)systems within a System-of-Systems(SoS)environment helps clarify their contribution to the overall combat capability and supports effectiveness-oriented system optimization.When assessing decision systems in such an environment,cross-level modeling and simulation are required,which often face a trade-off between low modeling cost and high simulation accuracy,while the credibility of results remains challenging to ensure.To address these issues,this study proposes a hybrid-granularity Hardware-In-the-Loop(HIL)SoS environment construction method based on Graphical Evaluation and Review Technique(GERT).The method employs GERT to analyze the relationships between simulation systems,the System Under Test(SUT),and mission outcomes,thereby determining the required model precision for different systems.A dynamic resource allocation algorithm is applied to adjust model granularity on demand,ensuring high-fidelity simulation under constrained total cost.Additionally,GERT estimates the computational frequency and communication bandwidth requirements of the SUT,guiding hardware selection to enhance simulation credibility.A UAV maritime combat case study was conducted for validation.The results demonstrate that,compared to the flat modeling approach,the hybrid-granularity scenario based on GERT analysis achieves higher simulation accuracy with lower overall model complexity.The coefficient of variation in evaluation results significantly decreases in HIL simulations compared to virtual simulations,confirming improved credibility.Under the hybrid-granularity HIL scenario,the decision system was evaluated from an effectiveness perspective,identifying the most sensitive performance parameter.Subsequent targeted optimization led to an 11.90%improvement in effectiveness,validating the method's practical utility.展开更多
Aircraft conceptual design is a critical step in the development and research of aircraft,involving complex processes and multiple disciplines.Improving the efficiency of aircraft conceptual design while ensuring qual...Aircraft conceptual design is a critical step in the development and research of aircraft,involving complex processes and multiple disciplines.Improving the efficiency of aircraft conceptual design while ensuring quality is an important challenge.Intelligent technologies such as neural networks have played significant roles in areas like aerodynamics and structural analysis.However,due to issues such as high data demands and difficulties in transfer learning,their application in the conceptual design phase has been limited.The rise of generative artificial intelligence,exemplified by Large Language Model(LLM),offers a new approach to this problem.Therefore,this study proposes a methodology for generating aircraft conceptual design solutions based on LLMs and develops a prototype system.First,four of the current best-performing general-purpose LLMs are selected for deployment as foundational models.Then,based on the general prompt framework of LLMs,schema for aircraft conceptual design solutions,and real-world design cases,task prompts for generating aircraft conceptual design solutions are crafted,resulting in three types of prompts:Full-Instruction,1-Shot,and 5-Shot.Finally,the prototype system is utilized to design conceptual solutions,and the model-generated solutions are compared with those designed by engineers from both objective and subjective perspectives.The experimental results indicate that LLMs demonstrate conceptual design capabilities comparable to those of engineers,exhibiting strong generalization ability and potential for innovative design.展开更多
Aircraft collaboration design is based on a unified set of schemas containing data and model representations and interfaces across disciplines.The aircraft design schema is a central data model that specifies the para...Aircraft collaboration design is based on a unified set of schemas containing data and model representations and interfaces across disciplines.The aircraft design schema is a central data model that specifies the paradigm for the representation of a full lifecycle model of aircraft design.The construction of the schema currently lacks theoretical guidance.This paper designs a novel methodology to construct the aircraft design schema,a fully functional,logical,and selfconsistent methodology.The methodology defines a schema matrix that includes implementation strategies,principles,processes,meta-object facility,views,scenarios,and products.The aircraft conceptual design schema is constructed according to the methodology,which is a hands-on approach to help understand the concept and implementation.The features of the methodology are analyzed,and the methodology and the aircraft conceptual design schema are presented to address the pain points of multiple solution trade-offs,multiple iterations,and multidisciplinary coupling in aircraft conceptual collaboration design.展开更多
With the rapid development of the low-altitude economy,electric Vertical Take-off and Landing(eVTOL)aircraft have emerged as a key focus of advanced air mobility.Open rotor and ducted fan configurations are the two pr...With the rapid development of the low-altitude economy,electric Vertical Take-off and Landing(eVTOL)aircraft have emerged as a key focus of advanced air mobility.Open rotor and ducted fan configurations are the two primary types,but their distinct effects on aerodynamic performance and stability require thorough quantitative investigation.This study establishes a high-fidelity computational framework based on the Reynolds-Averaged Navier-Stokes(RANS)equations,incorporating eddy viscosity corrections and the Multiple Reference Frame(MRF)method to accurately resolve the interactional flow fields between the open rotor/ducted fan and the airframe.The results demonstrate that the open rotor configuration significantly enhances the cruise lift-to-drag ratio,thereby improving cruise efficiency.In contrast,the ducted fan configuration exhibits superior pitch and yaw static stability,especially under crosswind conditions.The ducted fan generates a nose-down pitching moment and contributes to improved directional stability.However,both configurations are found to compromise roll stability.Quantitatively,this study clarifies the complementary advantages of open rotor and ducted fan systems in terms of efficiency enhancement and stability performance,providing valuable insights for propulsion system selection and conceptual design of eVTOL aircraft.展开更多
Stability is essential for the safety of Unmanned Aerial Vehicles(UAVs)and holds paramount importance in their design.This study focuses on the longitudinal stability of twin-boom UAVs with inverted V-tail and inverte...Stability is essential for the safety of Unmanned Aerial Vehicles(UAVs)and holds paramount importance in their design.This study focuses on the longitudinal stability of twin-boom UAVs with inverted V-tail and inverted U-tail configurations.Computational fluid dynamics(CFD)method and longitudinal perturbed equations of motion were employed to compre-hensively analyze the stability and flight performance of these UAVs.Results indicate that the inverted U-tail configuration exhibits 23.6% higher longitudinal static stability than the inverted V-tail under small perturbations.In Phugoid mode,the inverted U-tail UAV also demonstrates superior performance.These findings provide valuable insights for the design and optimization of UAV tail configurations.展开更多
基金funded by Henan Key Laboratory of General Aviation Technology,grant number ZHKF-240202。
文摘Evaluating Unmanned Aerial Vehicle(UAV)systems within a System-of-Systems(SoS)environment helps clarify their contribution to the overall combat capability and supports effectiveness-oriented system optimization.When assessing decision systems in such an environment,cross-level modeling and simulation are required,which often face a trade-off between low modeling cost and high simulation accuracy,while the credibility of results remains challenging to ensure.To address these issues,this study proposes a hybrid-granularity Hardware-In-the-Loop(HIL)SoS environment construction method based on Graphical Evaluation and Review Technique(GERT).The method employs GERT to analyze the relationships between simulation systems,the System Under Test(SUT),and mission outcomes,thereby determining the required model precision for different systems.A dynamic resource allocation algorithm is applied to adjust model granularity on demand,ensuring high-fidelity simulation under constrained total cost.Additionally,GERT estimates the computational frequency and communication bandwidth requirements of the SUT,guiding hardware selection to enhance simulation credibility.A UAV maritime combat case study was conducted for validation.The results demonstrate that,compared to the flat modeling approach,the hybrid-granularity scenario based on GERT analysis achieves higher simulation accuracy with lower overall model complexity.The coefficient of variation in evaluation results significantly decreases in HIL simulations compared to virtual simulations,confirming improved credibility.Under the hybrid-granularity HIL scenario,the decision system was evaluated from an effectiveness perspective,identifying the most sensitive performance parameter.Subsequent targeted optimization led to an 11.90%improvement in effectiveness,validating the method's practical utility.
基金funded by Henan Key Laboratory of General Aviation Technology,China(No.ZHKF-240202).
文摘Aircraft conceptual design is a critical step in the development and research of aircraft,involving complex processes and multiple disciplines.Improving the efficiency of aircraft conceptual design while ensuring quality is an important challenge.Intelligent technologies such as neural networks have played significant roles in areas like aerodynamics and structural analysis.However,due to issues such as high data demands and difficulties in transfer learning,their application in the conceptual design phase has been limited.The rise of generative artificial intelligence,exemplified by Large Language Model(LLM),offers a new approach to this problem.Therefore,this study proposes a methodology for generating aircraft conceptual design solutions based on LLMs and develops a prototype system.First,four of the current best-performing general-purpose LLMs are selected for deployment as foundational models.Then,based on the general prompt framework of LLMs,schema for aircraft conceptual design solutions,and real-world design cases,task prompts for generating aircraft conceptual design solutions are crafted,resulting in three types of prompts:Full-Instruction,1-Shot,and 5-Shot.Finally,the prototype system is utilized to design conceptual solutions,and the model-generated solutions are compared with those designed by engineers from both objective and subjective perspectives.The experimental results indicate that LLMs demonstrate conceptual design capabilities comparable to those of engineers,exhibiting strong generalization ability and potential for innovative design.
文摘Aircraft collaboration design is based on a unified set of schemas containing data and model representations and interfaces across disciplines.The aircraft design schema is a central data model that specifies the paradigm for the representation of a full lifecycle model of aircraft design.The construction of the schema currently lacks theoretical guidance.This paper designs a novel methodology to construct the aircraft design schema,a fully functional,logical,and selfconsistent methodology.The methodology defines a schema matrix that includes implementation strategies,principles,processes,meta-object facility,views,scenarios,and products.The aircraft conceptual design schema is constructed according to the methodology,which is a hands-on approach to help understand the concept and implementation.The features of the methodology are analyzed,and the methodology and the aircraft conceptual design schema are presented to address the pain points of multiple solution trade-offs,multiple iterations,and multidisciplinary coupling in aircraft conceptual collaboration design.
基金funded by Foundation of National Key Laboratory of Aircraft Configuration Design(No.JBGS-202501)Henan Provincial Science and Technology Research Project(No.252102220060)Henan Provincial Talent Support Program(No.254000510003).
文摘With the rapid development of the low-altitude economy,electric Vertical Take-off and Landing(eVTOL)aircraft have emerged as a key focus of advanced air mobility.Open rotor and ducted fan configurations are the two primary types,but their distinct effects on aerodynamic performance and stability require thorough quantitative investigation.This study establishes a high-fidelity computational framework based on the Reynolds-Averaged Navier-Stokes(RANS)equations,incorporating eddy viscosity corrections and the Multiple Reference Frame(MRF)method to accurately resolve the interactional flow fields between the open rotor/ducted fan and the airframe.The results demonstrate that the open rotor configuration significantly enhances the cruise lift-to-drag ratio,thereby improving cruise efficiency.In contrast,the ducted fan configuration exhibits superior pitch and yaw static stability,especially under crosswind conditions.The ducted fan generates a nose-down pitching moment and contributes to improved directional stability.However,both configurations are found to compromise roll stability.Quantitatively,this study clarifies the complementary advantages of open rotor and ducted fan systems in terms of efficiency enhancement and stability performance,providing valuable insights for propulsion system selection and conceptual design of eVTOL aircraft.
基金funded by the Science and Technology Project of Henan Province,grant number 232102220029Henan Key Laboratory of General Aviation Technology,grant number ZHKF-240202,240211.
文摘Stability is essential for the safety of Unmanned Aerial Vehicles(UAVs)and holds paramount importance in their design.This study focuses on the longitudinal stability of twin-boom UAVs with inverted V-tail and inverted U-tail configurations.Computational fluid dynamics(CFD)method and longitudinal perturbed equations of motion were employed to compre-hensively analyze the stability and flight performance of these UAVs.Results indicate that the inverted U-tail configuration exhibits 23.6% higher longitudinal static stability than the inverted V-tail under small perturbations.In Phugoid mode,the inverted U-tail UAV also demonstrates superior performance.These findings provide valuable insights for the design and optimization of UAV tail configurations.
