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Applying the disciplinary relation matrix to multidisciplinary design optimization modeling and solving

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Journal of Systems Engineering and Electronics 2017年第4期28卷 703-716页

作者： Hua Su Liangxian Gu chunlin gong Shaanxi Aerospace Flight Vehicle Design Key Laboratory Northwestern Polytechnical University Xi’an 710072 China

A new efficient coupling relationship description method has been developed to provide an automated and visualized way to multidisciplinary design optimization (MDO) modeling and solving. The disciplinary relation matrix (DRM) is proposed to describe the coupling relationship according to disciplinary input/output variables, and the MDO definition has been reformulated to adopt the new interfaces. Based on these, a universal MDO solving procedure is proposed to establish an automated and efficient way for MDO modeling and solving. Through a simple and convenient initial configuration, MDO problems can be solved using any of available MDO architectures with no further effort. Several examples are used to verify the proposed MDO modeling and solving process. Result shows that the DRM method has the ability to simplify and automate the MDO procedure, and the related MDO framework can evaluate the MDO problem automatically and efficiently.

关键词： multidisciplinary design optimization (MDO) problem definition solution architecture solving automation

Dynamics of a deflectable-nose missile

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Science China(Technological Sciences) 2012年第12期55卷 3483-3494页

作者： SUN XiaoFeng GU LiangXian gong chunlin School of Astronautics Northwestern Polytechnical UniversityXi'an 710072China

The dynamics of a supersonic missile with a deflectable nose are studied. To describe the effects of nose deflection on the dynamic model, theorems of momentum and angular momentum are adopted to develop the translational equation and rotation equation, respectively. Because the exact model is complex, it is simplified. The simplified model suggests that the main influence of nose deflection on the dynamic model is due to the product of the time derivatives of the azimuth angle and the elevation angle, which makes the dynamic model an impulsive differential system. Considering the aerodynamic characteristics a numerical simulation is sufficient to show the open-loop characteristics of the missile.

关键词： dynamics deflectable nose morphing missile theorems of momentum and angular momentum impulsive differential system

Design methodology of a mini-missile considering flight performance and guidance precision

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Journal of Systems Engineering and Electronics 2024年第1期35卷 195-210页

作者： ZHANG Licong gong chunlin SU Hua ANDREA Da Ronch Shaanxi Aerospace Flight Vehicle Design Key Laboratory School of AstronauticsNorthwestern Polytechnical UniversityXi’an 710072China Faculty of Engineering and Physical Sciences University of SouthamptonSouthampton SO171BJUnited Kingdom

The design of mini-missiles(MMs)presents several novel *** stringent mission requirement to reach a target with a certain precision imposes a high guidance *** miniaturization of the size of MMs makes the design of the guidance,navigation,and control(GNC)have a larger-thanbefore impact on the main-body design(shape,motor,and layout design)and its design objective,i.e.,flight *** a trade-off between flight performance and guidance precision,all the relevant interactions have to be accounted for in the design of the main body and the GNC ***,a multi-objective and multidisciplinary design optimization(MDO)is *** pertinent to motor,aerodynamics,layout,trajectory,flight dynamics,control,and guidance are included in the proposed MDO *** optimization problem seeks to maximize the range and minimize the guidance *** problem is solved by using the nondominated sorting genetic algorithm *** optimum design that balances a longer range with a smaller guidance error is ***,lessons learned about the design of the MM and insights into the trade-off between flight performance and guidance precision are given by comparing the optimum design to a design provided by the traditional approach.

关键词： mini-missiles(MMs) guidance navigation and control(GNC)system multi-objective optimization multidisciplinary design optimization(MDO) flight performance guidance precision

A study of morphing aircraft on morphing rules along trajectory

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Chinese Journal of Aeronautics 2021年第7期34卷 232-243页

作者： Xiaoyu CHEN Chunna LI chunlin gong Liangxian GU Andrea Da RONCH Shaanxi Aerospace Flight Vehicle Design Key Laboratory School of AstronauticsNorthwestern Polytechnical UniversityXi’an 710072China University of Southampton Southampton SO171BJUnited Kingdom

Morphing aircraft can meet requirements of multi-mission during the whole flight due to changing the aerodynamic shape,so it is necessary to study itsmorphing rules along the ***,trajectory planning considering morphing variables requires a huge number of expensive CFD computations due to the morphing in view of aerodynamic *** the given missions and trajectory,to alleviate computational cost and improve trajectory-planning efficiency formorphing aircraft,an offline optimizationmethod is proposed based onMulti-Fidelity Kriging(MFK)*** angle of attack,Mach number,sweep angle and axial position of the morphing wing are defined as variables for generating training data for building the MFK models,in which many inviscid aerodynamic solutions are used as low-fidelity data,while the less high-fidelity data are obtained by solving viscous *** the built MFK models of the lift,drag and pressure centre at the different angles of attack andMach numbers are used to predict the aerodynamic performance of the morphing aircraft,which keeps the optimal sweep angle and axial position of the wing during trajectory ***,themorphing rules can be correspondingly acquired along the trajectory,aswell as keep the aircraftwith the best aerodynamic performance during thewhole *** trajectory planning of amorphing aircraft was performed with the optimal aerodynamic performance based on the MFK models,built by only using 240 low-fidelity data and 110 high-fidelity *** results indicate that a complex trajectory can take advantage of morphing rules in keeping good aerodynamic performance,and the proposed method is more efficient than trajectory optimization by reducing 86%of the computing time.

关键词： Aerodynamic Morphing wing Multi-fidelity Kriging model Offline optimization Trajectory planning

An efficient uncertainty propagation method for nonlinear dynamics with distribution-free P-box processes

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Chinese Journal of Aeronautics 2024年第12期37卷 116-138页

作者： Licong ZHANG Chunna LI Hua SU Yuannan XU Andrea Da RONCH chunlin gong Flight Vehicle Design Key Laboratory School of AstronauticsNorthwestern Polytechnical UniversityXi’an 710072China Research and Development Department China Academy of Launch Vehicle TechnologyBeijing 100076China Faculty of Engineering and Physical Sciences University of SouthamptonSouthamptonEngland SO171BJUK

The distribution-free P-box process serves as an effective quantification model for timevarying uncertainties in dynamical systems when only imprecise probabilistic information is ***,its application to nonlinear systems remains limited due to excessive *** work develops an efficient method for propagating distribution-free P-box processes in nonlinear ***,using the Covariance Analysis Describing Equation Technique(CADET),the dynamic problems with P-box processes are transformed into interval Ordinary Differential Equations(ODEs).These equations provide the Mean-and-Covariance(MAC)bounds of the system responses in relation to the MAC bounds of P-box-process *** also separate the previously coupled P-box analysis and nonlinear-dynamic simulations into two sequential steps,including the MAC bound analysis of excitations and the MAC bounds calculation of responses by solving the interval ***,a Gaussian assumption of the CADET is extended to the P-box form,i.e.,the responses are approximate parametric Gaussian P-box *** a result,the probability bounds of the responses are approximated by using the solutions of the interval ***,the Chebyshev method is introduced and modified to efficiently solve the interval *** proposed method is validated based on test cases,including a duffing oscillator,a vehicle ride,and an engineering black-box problem of launch vehicle *** to the reference solutions based on the Monte Carlo method,with relative errors of less than 3%,the proposed method requires less than 0.2% calculation *** proposed method also possesses the ability to handle complex black-box problems.

关键词： Nonlinear dynamics Uncertainty propagation Imprecise probability Distribution-free P-box processes Chebyshev method

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基于高拟真度模型的再入飞行器多学科优化

西北工业大学学报 2013年第3期31卷 339-344页

作者：粟华谷良贤龚春林西北工业大学航天学院陕西西安710072

针对新型飞行器子学科高度集成、学科间强烈耦合的设计特点,提出了一套基于高拟真度学科分析模型的高超声速飞行器多学科建模、集成和求解方法。采用依托CAD造型的参数化主模型架构技术进行几何特征建模,为气动、结构、气动热、质量等... 详细信息

针对新型飞行器子学科高度集成、学科间强烈耦合的设计特点,提出了一套基于高拟真度学科分析模型的高超声速飞行器多学科建模、集成和求解方法。采用依托CAD造型的参数化主模型架构技术进行几何特征建模,为气动、结构、气动热、质量等学科分析模型构建提供基准支持;在此基础上研究了CAD、CAE等高拟真度学科分析模型在多学科设计优化中的集成应用方法,并以高超声速无动力滑翔再入飞行器为对象建立了支持高拟真度模型的多学科优化系统构架;最后采用响应面与梯度算法组合的搜索方式实现了再入飞行器的多学科优化。

关键词：多学科优化高拟真度模型参数化主模型技术参数化方法集成技术高超声速飞行器

改进自动微分方法及其在飞行器气动外形优化中的应用

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西北工业大学学报 2007年第3期25卷 398-401页

作者：潘雷谷良贤龚春林西北工业大学航天学院陕西西安710072

在飞行器设计优化过程中存在大量的梯度计算,简单高效的梯度计算方法可以很大地提高飞行器的优化效率。自动微分法是一种无需人工干预的高效梯度算法,为了进一步提高自动微分方法的计算效率,在函数首次执行后,形成单独的梯度计算过程,... 详细信息

在飞行器设计优化过程中存在大量的梯度计算,简单高效的梯度计算方法可以很大地提高飞行器的优化效率。自动微分法是一种无需人工干预的高效梯度算法,为了进一步提高自动微分方法的计算效率,在函数首次执行后,形成单独的梯度计算过程,并采用矩阵的方式对该过程进行存储和调用。应用改进后的自动微分程序对某飞行器的弹翼外形进行基于梯度的优化,计算结果表明,改进后的程序计算精度与传统方法相同,计算速度可提高2倍以上,对于工程中常见的大规模稀疏问题计算效率可高达传统算法的3倍左右。

关键词：梯度自动微分优化飞行器

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动能拦截器姿控与轨控方案设计及仿真

西北工业大学学报 2007年第3期25卷 402-405页

作者：谷良贤龚春林郝波西北工业大学航天学院陕西西安710072

针对大气层外动能拦截导弹,建立了连续脉冲、间隔脉冲和单脉冲3种姿、轨控发动机推力模型,从减小发动机开关频率和提高制导精度着手,设计了发动机的开关门限控制规律。对动能拦截器末制导段弹道进行了仿真。结果表明,在目标不机动的情况... 详细信息

针对大气层外动能拦截导弹,建立了连续脉冲、间隔脉冲和单脉冲3种姿、轨控发动机推力模型,从减小发动机开关频率和提高制导精度着手,设计了发动机的开关门限控制规律。对动能拦截器末制导段弹道进行了仿真。结果表明,在目标不机动的情况下,靠姿、轨控发动机提供的机动过载,可实现动能拦截器与目标的直接碰撞;在目标机动的情况下,受姿、轨控发动机推力大小和开关机次数的限制,直接侧向力提供机动过载和维持姿态稳定的能力有限,为使脱靶量达到最小,应优化选择动能拦截器在中末制导交班时刻的弹道倾角和弹体姿态角。

关键词：动能拦截器推力模型轨道控制姿态控制

Fluid-structure interaction simulation for flexible structures with immersed boundary-lattice Boltzmann and finite element method

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Fluid-structure interaction simulation for flexible structur...