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integrated optimization on aerodynamics-structure coupling and flight stability of a large airplane in preliminary design

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Chinese Journal of Aeronautics 2018年第6期31卷 1258-1272页

作者： Xiaozhe WANG Zhiqiang WAN Zhu LIU Chao YANG School of Aeronautic Science and Engineering Beihang University Key Laboratory of Aircraft Advanced Design Technology Ministry of Industry and Information

The preliminary phase is significant during the whole design process of a large airplane because of its enormous potential in enhancing the overall performance. However, classical sequential designs can hardly adapt to modern airplanes, due to their repeated iterations, long periods, and massive computational burdens. Multidisciplinary analysis and optimization demonstrates the capability to tackle such complex design issues. In this paper, an integrated optimization method for the preliminary design of a large airplane is proposed, accounting for aerodynamics, structure, and stability. Aeroelastic responses are computed by a rapid three-dimensional flight load analysis method combining the high-order panel method and the structural elasticity correction. The flow field is determined by the viscous/inviscid iteration method, and the cruise stability is evaluated by the linear small-disturbance theory. Parametric optimization is carried out using genetic algorithm to seek the minimal weight of a simplified plate-beam wing structure in the cruise trim condition subject to aeroelastic, aerodynamic, and stability constraints, and the optimal wing geometry shape, front/rear spar positions, and structural sizes are obtained simultaneously. To reduce the computational burden of the static aeroelasticity analysis in the optimization process, the Kriging method is employed to predict aerodynamic influence coefficient matrices of different aerodynamic shapes. The multidisciplinary analyses guarantee computational accuracy and efficiency, and the integrated optimization considers the coupling effect sufficiently between different disciplines to improve the overall performance, avoiding the limitations of sequential approaches utilized currently.

关键词： Aeroelasticity integrated optimization Multidisciptinary analysis Large airplane Preliminary design

integrated optimization of multiproduct multiperiod transportation and inventory under a carbon cap constraint for online retailers

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Transportation Safety and Environment 2021年第3期3卷 291-303页

作者： Yaorong Cheng Yijun Li School of Traffic&Transportation Engineering Central South UniversityChangsha 410075China

This study aims to solve the problem of multiproduct multiperiod integrated transportation and inventory optimization for online retailers.A carbon cap constraint and multitype of capacitated trucks are simultaneously incorporated into the proposed mixed-integer program.A simulated annealing(SA)algorithm is designed.CPLEX 12.9.0 is used to solve the submodel obtained from the neighbourhood search and is also used to get the optimal solutions for instances.Experimental results show that the simulated annealing algorithm can find satisfactory solutions within a reasonable time.When the problem size increases,the growth of the computational time of the SA algorithm is significantly smaller than that of the CPLEX.A sensitivity analysis for the carbon cap is also conducted.The results indicate that if the carbon cap is gradually tightened,the total cost increases first with a gentle slope,and then with a remarkable slope,same as for the total number of trucks used;the total carbon emissions first decrease with a gentle slope,and then decline with a significant slope.When the carbon cap is strict,only a few different types of trucks will be considered.The percentage changes of the total cost increase and the total carbon emission reduction are also compared.When the allowed carbon emissions are gradually reduced,situation of a higher amount of carbon emission reduction and a lower amount of cost increase can be achieved.Additionally,using multiple types of trucks in the integrated optimization of transportation and inventory decisions can achieve greater cost savings with lower increments of carbon emission.

关键词： integrated optimization multiperiod multiproduct carbon emission simulated annealing

integrated optimization of Structure and Control Parameters for the Height Control System of a Vertical Spindle Cotton Picker

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Chinese Journal of Mechanical Engineering 2021年第6期34卷 405-416页

作者： Xingzheng Chen Congbo Li Rui Hu Ning Liu Chi Zhang College of Engineering and Technology Southwest UniversityChongqing400715China State Key Laboratory of Mechanical Transmission Chongqing UniversityChongqing400044China Department of Mechanical Engineering National University of SingaporeSingapore119077Singapore

Vertical picking method is a predominate method used to harvest cotton crop.However,a vertical picking method may cause spindle bending of the cotton picker if spindles collide with stones on the cotton field.Thus,how to realize a precise height control of the cotton picker is a crucial issue to be solved.The objective of this study is to design a height control system to avoid the collision.To design it,the mathematical models are established first.Then a multi-objective optimization model represented by structure parameters and control parameters is proposed to take the pressure of chamber without piston,response time and displacement error of the height control system as the opti-mization objectives.An integrated optimization approach that combines optimization via simulation,particle swarm optimization and simulated annealing is proposed to solve the model.Simulation and experimental test results show that the proposed integrated optimization approach can not only reduce the pressure of chamber without piston,but also decrease the response time and displacement error of the height control system.

关键词： Cotton picker Height control system Structure parameters Control parameters integrated optimization

integrated optimization methods in multisensor decision and estimation fusion

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Science China(Information Sciences) 2012年第3期55卷 545-550页

作者： LUO YingTing, SHEN XiaoJing & ZHU YunMin College of Mathematics, Sichuan University Chengdu, 610064, China College of Mathematics Sichuan University Chengdu China

This paper presents a significant integrated optimization point of view behind the following three successful decision and estimation fusion results: 1) a unified fusion rule for networked sensor decision systems; 2) optimal sensor data quantization for estimation fusion and 3) integrated multi-target data association tracking systems. More precisely speaking, the integrated optimization method in 1) derives a unified objective function optimizing only sensor rules given a unified fusion rule; the method in 2) derives a unified objective function optimizing both the sensor quantization rule and the final estimation in the MSE sense, and the method in 3) integrates all associated targets and their valid observations into a whole random measurement matrix dynamic system so that the optimal random matrix Kalman filtering can be applied to estimate the states of all associated targets.

关键词： integrated optimization decision fusion estimation fusion data association

integrated batteries layout and structural topology optimization for a solar-powered drone

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Chinese Journal of Aeronautics 2021年第7期34卷 114-123页

作者： Zijian ZHANG Ruitong ZHANG Jihong ZHU Tong GAO Fei CHEN Weihong ZHANG Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China State IJR Center of Aerospace Design and Additive Manufacturing School of Mechanical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Institute of Intelligence Material and Structure Unmanned System TechnologiesNorthwestern Polytechnical UniversityXi’an 710072China

The purpose of this paper is to demonstrate an integrated optimization scheme for a solar-powered drone structure.Consider a primary beam in the wing of large aspect ratio,where 100 lithium batteries are assembled.In the proposed integrated optimization,the batteries are considered here as parts of the load-carrying structure.The corresponding mechanical behaviors are simulated in the structural design and described with super-elements.The batteries layout and the structural topology are then introduced as mixed design variables and optimized simultaneously to achieve an accordant load-carrying path.Geometrical nonlinearity is considered due to the large deformation.Different periodic structural configurations are tested in the optimization in order to meet the structural manufacturing and assembly convenience.The optimized designs are rebuilt and tested in different load cases.Maintaining the same structural weight,the global mechanical performances are improved greatly compared with the initial design.

关键词： Geometrical nonlinearity integrated optimization Lithium batteries layout Periodic structural configuration Solar-powered drone Wing beam structure

Novel integrated optimization algorithm for trajectory planning of robot manipulators based on integrated evolutionary programming

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控制理论与应用（英文版） 2004年第4期2卷 319-331页

作者： XiongLUO XiaopingFAN HengZHANG TefangCHEN CollegeofInformationScienceandEnoneermg CentralSouthUniversityChangshaHunan410083China

Optimal trajectory planning for robot manipulators plays an important role in implementing the high productivity for robots. The performance indexes used in optimal trajectory planning are classified into two main categories: optimum traveling time and optimum mechanical energy of the actuators. The current trajectory planning algorithms are designed based on one of the above two performance indexes. So far, there have been few planning algorithms designed to satisfy two performance indexes simultaneously. On the other hand, some deficiencies arise in the existing integrated optimi2ation algorithms of trajectory planning. In order to overcome those deficiencies, the integrated optimization algorithms of trajectory planning are presented based on the complete analysis for trajectory planning of robot manipulators. In the algorithm, two object functions are designed based on the specific weight coefficient method and ' ideal point strategy. Moreover, based on the features of optimization problem, the intensified evolutionary programming is proposed to solve the corresponding optimization model. Especially, for the Stanford Robot,the high-quality solutions are found at a lower cost.

关键词： Trajectory planning integrated optimization Evolutionary programming Robot manipulator

A new approach for flow simulation in complex hydraulic fracture morphology and its application:Fracture connection element method

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Petroleum Science 2023年第5期20卷 3002-3012页

作者： Guang-Long Sheng Hui Zhao Jia-Ling Ma Hao Huang Hai-Yang Deng Wen-Tao Zhan Yu-Yang Liu College of Petroleum Engineering Yangtze UniversityWuhan430100HubeiChina Hubei Key Laboratory of Oil and Gas Drilling and Production Engineering(Yangtze University) Wuhan430100HubeiChina China National Offshore Oil Corporation-Hainan Haikou570100HainanChina CNOOC Research Institute Ltd. Beijing100020China

Efficient flow simulation and optimization methods of hydraulic fracture morphology in unconventional reservoirs are effective ways to enhance oil/gas recovery.Based on the connection element method(CEM)and distribution of stimulated reservoir volume,the complex hydraulic fracture morphology was accurately described using heterogeneous node connection system.Then a new fracture connection element method(FCEM)for fluid flow in stimulated unconventional reservoirs with complex hydraulic fracture morphology was proposed.In the proposed FCEM,the arrangement of dense nodes in the stimulated area and sparse nodes in the unstimulated area ensures the calculation accuracy and efficiency.The key parameter,transmissibility,was also modified according to the strong heterogeneity of stimulated reservoirs.The finite difference and semi-analytical tracking were used to accurately solve the pressure and saturation distribution between nodes.The FCEM is validated by comparing with traditional numerical simulation method,and the results show that the bottom hole pressure simulated by the FCEM is consistent with the results from traditional numerical simulation method,and the matching rate is larger than 95%.The proposed FCEM was also used in the optimization of fracturing parameters by coupling the hydraulic fracture propagation method and intelligent optimization algorithm.The integrated intelligent optimization approach for multi-parameters,such as perforation number,perforation location,and displacement in hydraulic fracturing is proposed.The proposed approach was applied in a shale gas reservoir,and the result shows that the optimized perforation location and morphology distribution are related to the distribution of porosity/permeability.When the perforation location and displacement are optimized with the same fracture number,NPV increases by 70.58%,which greatly improves the economic benefits of unconventional reservoirs.This work provides a new way for flow simulation and optimization of hydraulic fracture morphology of m

关键词： Unconventional reservoirs Multi-fractured horizontal wells Complex fracture morphology Fracture connection element method integrated optimization

Design and optimization of the CFRP Mirror Components

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Photonic Sensors 2017年第3期7卷 270-277页

作者： Lei WEI Lei ZHANG Xiaoxue GONG University of Chinese Academy of Sciences Beijing 100039 China Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 China Chang Guang Satellite Technology LTD. Co Changchun 130000 China

As carbon fiber reinforced polymer （CFRP） material has been developed and demonstrated as an effective material in lightweight telescope reflector manufacturing recently, the authors of this article have extended to apply this material on the lightweight space camera mirror design and fabrication. By CFRP composite laminate design and optimization using finite element method （FEM） analysis, a spherical mirror with φ316 mm diameter whose core cell reinforcement is an isogrid configuration is fabricated. Compared with traditional ways of applying ultra-low-expansion glass （ULE） on the CFRP mirror surface, the method of nickel electroplating on the surface effectively reduces the processing cost and difficulty of the CFRP mirror. Through the FEM analysis, the first order resonance frequency of the CFRP mirror components reaches up to 652.3Hz. Under gravity affection coupling with ＋5℃ temperature rising, the mirror surface shape root-mean-square values （RMS） at the optical axis horizontal state is 5.74 nm, which meets mechanical and optical requirements of the mirror components on space camera.

关键词： Pure-CFRP mirror lay-up design bipod integrated optimization

Study on Inventory-Transportation integrated optimization in Distributing Network（ID:L-001）

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Study on Inventory-Transportation Integrated Optimization in...