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SUPERSONIC TRANSPORT WING MINIMUM WEIGHT DESIGN INTEGRATING AERODYNANAMICS AND STRUCTURES

JOURNAL OF AIRCRAFT 1994年第2期31卷 330-338页

作者： BARTHELEMY, JFM WRENN, GA DOVI, AR COEN, PG HALL, LE NASA Langley Research Center Hampton Virginia 23681 Lockheed Engineering and Sciences Company Hampton Virginia 23666 Unisys Corporation Hampton Virginia 23666

An approach is presented for determining the minimum weight design of aircraft wing models which takes into consideration aerodynamics-structure coupling when calculating both zeroth-order information needed for analysis and first-order information needed for optimization. When performing sensitivity analysis, coupling is accounted for by using a generalized sensitivity formulation. The results presented show that the aeroelastic effects are calculated properly and noticeably reduce constraint approximation errors. However, for the particular example selected, the error introduced by ignoring aeroelastic effects are not sufficient to significantly affect the convergence of the optimization process. Trade studies are reported that consider different structural materials, internal spar layouts, and panel buckling lengths. For the formulation, model, and materials used in this study, an advanced aluminum material produced the lightest design while satisfying the problem constraints. Also, shorter panel buckling lengths resulted in lower weights by permitting smaller panel thicknesses and generally, unloading the wing skins and loading the spar caps. Finally, straight spars required slightly lower wing weights than angled spars.

关键词： Aerodynamic Force Sensitivity Analysis Aircraft Wings Supersonic Transports Angle of Attack Camber sequential quadratic programming Aircraft Configurations Structural Analysis sequential Linear programming

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Clock Distribution Network Optimization by sequential quadratic Programing

Clock Distribution Network Optimization by Sequential Quadra...

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作者： Mekala, Venkata Texas A&M University

Clock mesh is widely used in microprocessor designs for achieving low clock skew and high process variation tolerance. Clock mesh optimization is a very diffcult problem to solve because it has a highly connected structure and requires accurate delay models which are computationally expensive. Existing methods on clock network optimization are either restricted to clock trees, which are easy to be separated into smaller problems, or naive heuristics based on crude delay models. A clock mesh sizing algorithm, which is aimed to minimize total mesh wire area with consideration of clock skew constraints, has been proposed in this research work. This algorithm is a systematic solution search through rigorous sequential quadratic programming (SQP). The SQP is guided by an efficient adjoint sensitivity analysis which has near-SPICE(Simulation Program for Integrated Circuits Emphasis)-level accuracy and faster-than-SPICE speed. Experimental results on various benchmark circuits indicate that this algorithm leads to substantial wire area reduction while maintaining low clock skew in the clock mesh. The reduction in mesh area achieved is about 33%.

关键词： Optimization Clock Distribution Network sequential quadratic programming Book Thesis

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Simulation and optimization of a continuous biodiesel plant using nonlinear programming

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ENERGY 2019年 189卷

作者： Alvardes, Adan de Oliveira Prata, Diego Martinez Santos, Lizandro de Sousa Univ Fed Fluminense Dept Engn Quim & Petr Rua Passo da Patria 156 BR-24210240 Niteroi RJ Brazil

The continuous production of biodiesel is achieved through a sequence of stages such as reaction, absorption, decantation, and product distillation. These steps require certain performance criteria that must be optimized. Several works have addressed the optimization of the design of biodiesel plants, and these have usually examined modifications to the dimensions and types of equipment or energy integration. However, there is only limited literature available on determining optimal operating conditions for existing processes. In this paper, the steady-state optimization of a soybean continuous biodiesel plant is proposed. To this end, a mathematical model to describe the chemical kinetics of soybean oil trans-esterification was developed and incorporated into a chemical process simulator. The optimization procedure is based on multidimensional sequential quadratic programming (SQP), in which the primary objectives were to minimize the plant's energy consumption subject to a minimum of 99 wt% biodiesel purity. The results reveal that the optimization of the current process allows a 4.45% reduction in energy consumption compared to the base case. Besides, the study also evidenced that the optimization approach can be applied to recalculate the optimal point when possible disturbances can deviate the system from a steady state. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： sequential quadratic programming Nonlinear programming Transesterification

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Design optimization for relative bandwidth of left-handed metamaterials with split-ring resonators

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JOURNAL OF OPTICS 2011年第1期13卷 015102-015102页

作者： Liu, Shutian Dong, Yanzhang Xu, Weikai Dalian Univ Technol State Key Lab Struct Anal Ind Equipment Dept Engn Mech Dalian 116024 Peoples R China

Due to their special properties, left-handed metamaterials have important potential applications in engineering. When an incident wave propagates through a periodic material with the dimension of its microstructure much smaller than the wavelength, the metamaterial can be regarded as a homogeneous medium, and its effective electromagnetic parameters (permittivity and permeability) in the frequency domain can be obtained with the S-parameters retrieval method. From this perspective, the design of a material with the desired left-handed characteristics becomes possible. By establishing automatic parametric modeling technology, we can study the transmission and reflection properties of left-handed metamaterials with arrays of split-ring resonators. Next, a whole flow chart of design optimization for improving left-handed metamaterial performance is proposed. Finally, the design method is illustrated through a numerical example including the shape and the size design of split-ring resonators to max relative bandwidth, based on parametric analysis of the left-handed relative bandwidths. sequential quadratic programming and enumeration optimization are applied to solve the optimization problem.

关键词： left-handed metamaterials material design relative bandwidth S-parameters retrieval methods sequential quadratic programming split-ring resonators

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A Fast Temporal Decomposition Procedure for Long- Horizon Nonlinear Dynamic programming

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MATHEMATICS OF OPERATIONS RESEARCH 2023年第2期49卷 653-1302, C2页

作者： Na, Sen Anitescu, Mihai Kolar, Mladen Univ Calif Berkeley Int Comp Sci Inst Berkeley CA 94720 USA Univ Calif Berkeley Dept Stat Berkeley CA 94720 USA Argonne Natl Lab Math & Comp Sci Div Lemont IL 60439 USA Univ Chicago Booth Sch Business Chicago IL 60637 USA

We propose a fast temporal decomposition procedure for solving long-horizon nonlinear dynamic programs. The core of the procedure is sequential quadratic programming (SQP) that utilizes a differentiable exact augmented Lagrangian as the merit function. Within each SQP iteration, we approximately solve the Newton system using an overlapping temporal decomposition strategy. We show that the approximate search direction is still a descent direction of the augmented Lagrangian provided the overlap size and penalty parameters are suitably chosen, which allows us to establish the global convergence. Moreover, we show that a unit step size is accepted locally for the approximate search direction and further establish a uniform, local linear convergence over stages. This local convergence rate matches the rate of the recent Schwarz scheme (Na et al. 2022). However, the Schwarz scheme has to solve nonlinear subproblems to optimality in each iteration, whereas we only perform a single Newton step instead. Numerical experiments validate our theories and demonstrate the superiority of our method.

关键词： nonlinear dynamic programming temporal decomposition sequential quadratic programming augmented Lagrangian

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A QCQP-based splitting SQP algorithm for two-block nonconvex constrained optimization problems with application

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JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS 2021年 390卷 113368-113368页

作者： Jian, Jinbao Liu, Pengjie Yin, Jianghua Zhang, Chen Chao, Miantao Guangxi Univ Nationalities Guangxi Key Lab Hybrid Computat & IC Design Anal Coll Math & Phys Ctr Appl Math & Artificial Intelligence Nanning 530006 Peoples R China Guangxi Univ Coll Math & Informat Sci Nanning 530004 Peoples R China Guangxi Sci & Technol Normal Univ Coll Math & Comp Sci Laibin 546199 Peoples R China Univ Shanghai Sci & Technol Sch Mech Engn Shanghai 200093 Peoples R China

This paper discusses a class of two-block nonconvex smooth optimization problems with nonlinear constraints. Based on a quadratically constrained quadratic programming (QCQP) approximation, an augmented Lagrangian function (ALF), and a Lagrangian splitting technique into small-scale subproblems, we propose a novel sequential quadratic programming (SQP) algorithm. First, inspired by the augmented Lagrangian method (ALM), we penalize the quadratic equality constraints associated with the QCQP approximation subproblem in its objective by means of the ALF, and then split the resulting subproblem into two small-scale ones, but both of them are not quadratic programming (QP) due to the square of the quadratic equality constraints in the objective. Second, by ignoring the three-order infinitesimal arising from the squared term, the two small-scale subproblems are reduced to two standard QP subproblems, which can yield an improved search direction. Third, taking the ALF of the discussed problem as a merit function, the next iterate point is generated by the Armijo line search. As a result, a new SQP method, called QCQP-based splitting SQP method, is proposed. Under suitable conditions, the global convergence, strong convergence, iteration complexity and convergence rate of the proposed method are analyzed and obtained. Finally, preliminary numerical experiments and applications were carried out, and these show that the proposed method is promising. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Two-block nonconvex constrained optimization quadratically constrained quadratic programming sequential quadratic programming Splitting method Convergence analysis

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Multidisciplinary Considerations in the Design of Wings and Wing Tip Devices

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JOURNAL OF AIRCRAFT 2010年第2期47卷 534-543页

作者： Ning, S. Andrew Kroo, Ilan Stanford Univ Dept Aeronaut & Astronaut Stanford CA 94305 USA

Conceptual wing design analysis methods are combined with numerical optimization to find minimum-drag wings subject to constraints on lift, weight, pitching moment, and stall speed. Tip extensions and winglets designed for minimum drag achieve similar performance, with the optimal solution depending on the ratio of the maneuver lift coefficient to the cruise lift coefficient. The results highlight the importance of accounting for the depth of the wing structural box in the weight model and including constraints on stall speed. For tailless aircraft, C-wings show a slight performance advantage over wings with winglets when longitudinal trim and stability constraints are considered. This performance advantage is more significant for span-constrained or low-sweep designs. Finally, to demonstrate other possible applications of the method, planar wings with active load alleviation are optimized, showing drag savings on the order of 15%.

关键词： Wing Tip Aerodynamic Center High Lift Device Lift Coefficient Lift to Drag Ratio Numerical Optimization Structural Load High Aspect Ratio Sweep Angle sequential quadratic programming

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A Combined Inverse Kinematics Algorithm Using FABRIK with Optimization

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JOURNAL OF INTELLIGENT & ROBOTIC SYSTEMS 2023年第4期108卷 62-62页

作者： Xu, Zichun Li, Yuntao Yang, Xiaohang Zhao, Zhiyuan Zhao, Jingdong Liu, Hong Harbin Inst Technol State Key Lab Robot & Syst Harbin 150001 Heilongjiang Peoples R China

Solving the inverse kinematics of redundant and hyper-redundant manipulators is more challenging because their kinematic redundancy leads to a more complicated mapping from end-effector pose to configuration space. A heuristic inverse kinematics solver, called Forward And Backward Reaching Inverse Kinematics (FABRIK), has been demonstrated to solve the inverse kinematics of complex chain systems with fast convergence and simple implementation. However, as the pose precision of the end-effector increases to a higher value, such as 10(-6), FABRIK converges slowly in some configurations and thus exhibits unstable convergence behavior. Hence, this paper presents a novel inverse kinematics algorithm that combines FABRIK and the sequential quadratic programming (SQP) algorithm, in which the joint angles deduced by FABRIK will be taken as the initial seed of the SQP algorithm to realize fast convergence. Meanwhile, a universal and non-trivial mapping from joint Cartesian positions to joint angles is included to enable the extension of FABRIK to redundant and hyper-redundant manipulators while retaining its simplicity. With the 10(-6) pose error constraint, quantitative tests on serial chain manipulators demonstrate that the combined algorithm outperforms FABRIK in terms of success rate and runtime. Meanwhile, some popular inverse kinematics algorithms are treated as benchmarks to compare with the combined algorithm. Finally, simulations using serial chain manipulators indicate the effectiveness of the combined algorithm on path tracking.

关键词： Inverse Kinematics Redundant Manipulators Hyper-Redundant Manipulators FABRIK sequential quadratic programming

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Reconstruction of Radiative Properties Fields in Participating Media by Using the sequential quadratic Programing Combined With Regularization Technique

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JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME 2019年第2期141卷 022702-022702页

作者： Wei, Lin-Yang Qi, Hong Zhang, Xiao-Luo Wen, Shuang Islam, Md Arafat Ruan, Li-Ming Harbin Inst Technol Sch Energy Sci & Engn Harbin 150001 Heilongjiang Peoples R China Minist Ind & Informat Technol Key Lab Aerosp Thermophys Harbin 150001 Heilongjiang Peoples R China

The refractive index and absorption coefficient fields in participating media are reconstructed simultaneously in this work. In the direct model, the coupled radiation-conduction heat transfer in participating media exposed to a pulse laser irradiation is solved by finite volume method (FVM). In the inverse model, the sequential quadratic programming (SQP) algorithm combined with the generalized Gaussian Markov random field (GGMRF) model is employed to solve the reconstruction problem. It is found that the refractive index and absorption coefficient fields cannot be reconstructed simultaneously. A secondary reconstruction technique based on different regularization parameters is proposed to reconstruct the refractive index and absorption coefficient fields simultaneously. All the retrieval results indicate that the proposed secondary reconstruction technique performs accurately and effectively.

关键词： inverse radiative problem refractive index field absorption coefficient field sequential quadratic programming regularization technique

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Interactive optimization tool for the optimum design of helical extension springs

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REVISTA TECNICA DE LA FACULTAD DE INGENIERIA UNIVERSIDAD DEL ZULIA 2009年第2期32卷 98-108页

作者： Galeano, Carlos H. Duque, Carlos A. Tovar, Andres Univ Nacl Colombia Dept Ingn Mecan & Mecatron Bogota Colombia

This work presents an interactive computer tool for the optimal design of helical extension springs. The developed algorithm incorporates all design considerations used in the manufacturing industry and specialized design manuals. All these considerations are used to create a novel optimum design formulation. The flexibility of this software allows the user to characterize a particular design problem, through the selection of the right constraints for each case. The optimization model includes sixteen constraints (linear and nonlinear) derived from different failure criteria and designs and manufacture recommendations. This nonlinear problem is solved using sequential quadratic programming in Matlab. The characteristics of this tool are showed through development of a benchmark problem. The free software developed in this work is available at http://***/optimun/resortes/.

关键词： Helical springs mechanical design sequential quadratic programming parametric design optimization

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