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An approach for formation design and flight performance prediction based on aerodynamic formation unit:Energy-saving considerations

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Chinese Journal of Aeronautics 2024年第3期37卷 77-91页

作者： Nanxuan QIAO tielin ma Xiangsheng WANG Jie WANG Jingcheng FU Pu XUE School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Institute of Unmanned System Beihang UniversityBeijing 100191China Key Laboratory of Advanced Technology of Intelligent Unmanned Flight System Ministry of Industry and Information TechnologyBeijing 100191China School of Transportation Science and Engineering Beihang UniversityBeijing 102206China Beijing Institute of Space Long march Vehicle Beijing 100076China

The performance improvement of swarm drones through aerodynamic shape optimization may be challenging due to folded size constraints imposed by the specific launch ***,fixed-wing aircraft swarms can benefit from formation flight in terms of energy *** study introduces the concept of the"aerodynamic formation unit",which consists of two or three aircraft that form an inseparable unit of the *** the Unmanned Aerial Vehicle(UAV)distribution and wingtip vortex interference in the formation,two typical aerodynamic formation units are optimized by the variable-fidelity aerodynamic optimization method based on space *** aerodynamic characteristics of the formation UAVs that affect flight performance,such as lift-to-drag ratio(L/D ratio)and static stability are analyzed by Computational Fluid Dynamics(CFD)*** L/D ratio(cruising condition)of the following aircraft can be increased by 22.8%and 57.5%in the optimal units that involve two and three aircraft ***,this study conducts several CFD simulations for multi-aircraft formations formed by the units,which show that the average L/D ratio of the formation can be improved by more than 19%.These results verify the feasibility and effectiveness of the"aerodynamic formation unit"concept and the optimization framework for formation parameters.

关键词： Formation flight CFD Aerodynamic formation unit Wingtip vortices Foldable tandem-wing aircraft

Unmanned aerial vehicle swarm mission reliability modeling and evaluation method oriented to systematic and networked mission

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Chinese Journal of Aeronautics 2021年第2期34卷 466-478页

作者： Lizhi WANG Xuejiao ZHAO Yuan ZHANG Xiaohong WANG tielin ma Xia GAO Unmanned System Institute Beihang UniversityBejing 100083China School of Reliability and Systems Engineering Beihang UniversityBeijing 100083China Digital Twinning and System Engineering Research Center Yunnan Innovation InstituteBeihang UniversityBejing 650233China Key Laboratory of Advanced Technology of Intelligent Unmanned Flight System of M inistry of Industry and Information Technology Beijing 100083China School of Astronautics Beihang UniversityBejing 100083China

With the development of Unmanned Aerial Vehicle(UAV) system autonomy, network communication technology and group intelligence theory, mission execution in the form of a UAV swarm will be an important realization of future applications. Traditional single-UAV mission reliability modeling methods have been unable to meet the requirements of UAV swarm mission reliability modeling. Therefore, the UAV swarm mission reliability modeling and evaluation method is proposed. First, aimed at the interdependence among the multiple layers, a multi-layer network model of a UAV swarm is established. At the same time, based on the system having the following characteristics—using a mission chain to complete the mission and applying the connectivity of the mission network—the mission network model of a UAV swarm is established. Second, vulnerability and connectivity are selected as two indicators to reflect the reliability of the mission, and aimed at random attack and deliberate attack, vulnerability and connectivity evaluation methods are proposed. Finally, the validity and accuracy of the constructed model are verified through simulations,and the model and selected indicators can meet the reliability requirements of the UAV swarm mission. In this way, this study provides quantitative reference for UAV-swarm-related decisionmaking work and supports the development of UAV-swarm-related work.

关键词： Complex networks Connectivity Mission reliability Unmanned Aerial Vehicles(UAV) Vulnerability

Static aeroelasticity of the propulsion system of ion propulsion unmanned aerial vehicles

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Propulsion and Power Research 2023年第3期12卷 336-355页

作者： Shuai Hao tielin ma She Chen Hongzhong ma Jinwu Xiang Fangxiang Ouyang School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Research Institute of Unmanned Systems Beihang UniversityBeijing 100191China Hiwing General Aviation Equipment Co. Ltd.Beijing 100074China College of Electrical and Information Engineering Hunan UniversityChangsha 410082China

“Ionic wind”generators are used as the main propulsion system in ion propulsion unmanned aerial vehicles(UAVs).Owing to the large size and poor stiffness of the electrode array in the propulsion system,the electrode array is prone to deformation under the flight *** this work,the thrust characteristics and static aeroelastic properties of“ionic wind”propulsion systems were analyzed in *** simulation model for an“ionic wind”propulsion system was established by coupling a two-dimensional gas discharge model with a gas dynamics *** influences of electrode voltage,spacing,size,and shape on the performance of the propulsion system were *** fluid-solid interaction method was used to solve static aeroelastic characteristics under *** aerodynamic and thrust performances of the elastic state and the rigid state were *** was found that the operating voltage,the distance between two electrodes,and the emitter radius had greater impacts on the thrust of the propulsion *** propulsion system had a small contribution to the lift but a large contribution to the *** the elastic state,the lift coefficient accounted for 12.2%,and the drag coefficient accounted for 25.8%.Under the action of the downwash airflow from the wing,the propulsion system formed an upward moment around the center of mass,which contributed greatly to the pitching moment derivative of the whole *** the elastic state,the pitching moment derivative accounted for 29.7%.After elastic deformation,the thrust action point moved upward by 28.7 ***,the no lift pitching moment is reduced by 0.104 N$m,and the pitching moment coefficient is reduced by 0.014,causing a great impact on the longitudinal trimming of the whole aircraft.

关键词： Ion propulsion unmanned aerial vehicle(UAV) Propulsion system Electro-aerodynamics Static aeroelasticity Fluid-solid interaction

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一种气动结构一体化设计方法

北京航空航天大学学报 2009年第11期35卷 1366-1370,1383页

作者：马铁林马东立张朔北京航空航天大学无人驾驶飞行器设计研究所北京100191 北京航空航天大学航空科学与工程学院北京100191

为解决气动结构一体化设计的工程应用,在传统并行子空间算法的基础上,深入分析了气动结构一体化设计的特点,在响应面构造上引入试验设计法,子空间优化中引入子空间设计的概念,系统级优化中引入Pareto遗传算法,提出了更加适合于气动结构... 详细信息

为解决气动结构一体化设计的工程应用,在传统并行子空间算法的基础上,深入分析了气动结构一体化设计的特点,在响应面构造上引入试验设计法,子空间优化中引入子空间设计的概念,系统级优化中引入Pareto遗传算法,提出了更加适合于气动结构多学科设计优化的基于Pareto遗传算法的并行子空间优化设计方法(CSSODM-PGA,Concurrent Sub-space Optimization Design Method based on Pareto Genetic Algorithm),并将算法应用到机翼的气动结构多学科设计优化中,给出了合理的Pareto前沿面和可选方案.

关键词：并行子空间算法 Pareto遗传算法多学科设计优化 Pareto前沿面

分析模型参数化建模在飞机多学科优化设计中的应用

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航空学报 2008年第6期29卷 1576-1580页

作者：马铁林马东立张朔北京航空航天大学航空科学与工程学院北京100191

论述分析模型参数化建模在飞机多学科优化设计中的重要意义,提出一种机翼气动与结构分析模型参数化建模方法。优化设计变量与机翼气动计算网格的中间参数变量用于描述机翼气动网格变形情况,并建立结构有限元网格与优化设计变量的空间变... 详细信息

论述分析模型参数化建模在飞机多学科优化设计中的重要意义,提出一种机翼气动与结构分析模型参数化建模方法。优化设计变量与机翼气动计算网格的中间参数变量用于描述机翼气动网格变形情况,并建立结构有限元网格与优化设计变量的空间变化关系,实现机翼气动/结构多学科优化设计模型的参数化描述。气动性能计算采用基于N-S方程的计算流体力学方法,利用试验设计方法(DOE)和响应曲面模型(RSM)技术构造气动响应曲面用于优化设计,结构计算调用MSC/NASTRAN完成。采用Pareto遗传算法对一大展弦比复合材料机翼模型进行了多学科优化设计分析,得到Pareto前沿面和可选方案以供决策者选择。

关键词：参数化建模多学科优化设计 Pareto前沿面大展弦比机翼

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弹性变形对柔性机翼气动特性影响分析

北京航空航天大学学报 2008年第5期34卷 487-490页

作者：张华马东立马铁林北京航空航天大学航空科学与工程学院北京100083

针对大展弦比全复合材料机翼的非线性静气弹响应行为,采用CFD/CSM(Computational Fluid Dynam ics/Computational Structural Mechanics)弱耦合方法,使用三维N-S方程和结构力学方程以及动网格生成技术和压强插值技术,通过高精度的数值模... 详细信息

针对大展弦比全复合材料机翼的非线性静气弹响应行为,采用CFD/CSM(Computational Fluid Dynam ics/Computational Structural Mechanics)弱耦合方法,使用三维N-S方程和结构力学方程以及动网格生成技术和压强插值技术,通过高精度的数值模拟,求解了大展弦比柔性机翼在结构几何非线性变形状态下的非线性静气弹响应问题.算例分别对典型的大展弦比复合材料前掠机翼和后掠机翼进行了求解,计算结果表明,与前掠翼相比,后掠翼的升力系数明显降低,升阻比降低,严重偏离了刚性机翼的设计点,在柔性机翼的气动设计中必须加以考虑.

关键词：机翼空气动力学柔性结构结构变形

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大展弦比柔性机翼气动特性分析

北京航空航天大学学报 2007年第7期33卷 781-784页

作者：马铁林马东立张华北京航空航天大学航空科学与工程学院北京100083

长航时无人机在飞行过程中受气动载荷影响,其大展弦比机翼产生弯曲和扭转变形,这种弹性变形严重影响飞机的飞行性能和飞行安全,不能将此种飞机机翼当作传统的刚性机翼进行气动分析.针对一真实复合材料大展弦比前掠机翼,采用气动/结构一... 详细信息

长航时无人机在飞行过程中受气动载荷影响,其大展弦比机翼产生弯曲和扭转变形,这种弹性变形严重影响飞机的飞行性能和飞行安全,不能将此种飞机机翼当作传统的刚性机翼进行气动分析.针对一真实复合材料大展弦比前掠机翼,采用气动/结构一体化的分析方法,利用计算流体动力学(CFD)软件FLUENT和计算结构动力学(CSD)软件NASTRAN联合求解,研究了在不同载荷情况下大展弦比柔性机翼静气动弹性变形对机翼气动特性的影响.结果表明,大展弦比无人机机翼受载变形后升阻比降低,滚转力矩和偏航力矩显著增大,对飞机的纵向和横侧向气动性能产生不利影响,同时也证明此CFD/CSD耦合计算方法可以应用到柔性机翼的气动/结构一体化设计中.

关键词： CFD/CSD 大展弦比柔性机翼静气动弹性气动特性一体化设计

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一种联结翼布局气动特性的求解模型

航空学报 2010年第5期31卷 909-913页

作者：楚亮马东立张朔马铁林北京航空航天大学航空科学与工程学院北京100191 北京航空航天大学无人机所北京100191

联结翼布局与常规布局相比具有结构重量轻、诱导阻力小、升力系数大和稳定性良好的特点。从升力线理论出发,引入普朗特对干扰因子的假设,推导出适合于平列式联结翼布局的气动求解模型,并给出了干扰因子的取值范围。该模型保持了工程估... 详细信息

联结翼布局与常规布局相比具有结构重量轻、诱导阻力小、升力系数大和稳定性良好的特点。从升力线理论出发,引入普朗特对干扰因子的假设,推导出适合于平列式联结翼布局的气动求解模型,并给出了干扰因子的取值范围。该模型保持了工程估算方法所具有的简单、快捷的优势,与计算流体力学(CFD)计算结果的对比显示,模型具有较好的精度。研究结果表明,在机翼面积不变的情况下,增大前翼展弦比、展长比及翼隔可有效降低总诱导阻力,与单翼布局相比诱导阻力最大可降低28%。

关键词：联结翼气动模型干扰因子工程估算计算流体力学

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某无人机气动估算与风洞试验

北京航空航天大学学报 2006年第12期32卷 1399-1402,1417页

作者：马东立马铁林刘薇薇北京航空航天大学航空科学与工程学院北京100083

基于气动估算和风洞试验相结合的方法,研究某型无人机的气动特性.通过不同V形尾翼纵向力矩对比试验,发现尾翼上反角对纵向力矩特性影响较大,并分析了纵向力矩曲线上翘的原因.进行飞机部件及全机气动性能对比试验,给出V形尾翼无人机气动... 详细信息

基于气动估算和风洞试验相结合的方法,研究某型无人机的气动特性.通过不同V形尾翼纵向力矩对比试验,发现尾翼上反角对纵向力矩特性影响较大,并分析了纵向力矩曲线上翘的原因.进行飞机部件及全机气动性能对比试验,给出V形尾翼无人机气动估算方法,找出计算与试验结果产生差别的原因,通过调整尾翼安装角,优化了无人机的气动特性.同时风洞试验也证明所采用的气动估算方法是可信的,可用于此类布局无人机的气动计算.

关键词：无人机气动估算风洞试验 V形尾翼