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Integrated optimization design of smart morphing wing for accurate shape control

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Chinese Journal of Aeronautics 2021年第1期34卷 135-147页

作者： Xiaojun GU Kaike YANG Manqiao WU Yahui zhang Jihong ZHU weihong zhang Unmanned System Research Institute Northwestern Polytechnical UniversityXi'an 710072China State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Poly technical UniversityXi'an 710072China Science and Technology on Space Physics Laboratory China Academy of Launch Vehicle TechnologyBeijing 100076China

Smart morphing wing, which is equipped with smart materials and able to change structural geometry adaptively, can further improve aerodynamic efficiency of aircraft. This paper presents a new integrated layout and topology optimization design for morphing wing driven by shape memory alloys(SMAs). By simultaneously optimizing the layout of smart actuators and topology of wing substrate, the ultimately determined configuration can achieve smooth, continuous and accurate geometric shape changes. In addition, aerodynamic analysis is carried out to compare smart morphing wing with traditional hinged airfoil. Finally, the optimized smart wing structure is constructed and tested to demonstrate and verify the morphing functionality. Application setbacks are also pointed out for further investigation.

关键词： Layout optimization Morphing wing Shape memory alloy Shape morphing Topology optimization

Topology optimization of joint load control with geometrical nonlinearity

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Chinese Journal of Aeronautics 2020年第1期33卷 372-382页

作者： Jie HOU Xiaojun GU Jihong ZHU Jie WANG weihong zhang State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical University710072 Xi’anChina Institute of Intelligence Material and Structure Unmanned System TechnologiesNorthwestern Polytechnical University710072 Xi’anChina MIIT Lab of Metal Additive Manufacturing and Innovative Design Northwestern Polytechnical University710072 Xi’anChina

This paper presents an extended topology optimization approach considering joint load constraints with geo-metrical nonlinearity in design of assembled *** geometrical nonlinearity is firstly included to reflect the structural response and the joint load distribution under large *** avoid a failure of fastener joints,topology optimization is then carried out to minimize the structural end compliance in the equilibrium state while controlling joint loads intensities over *** nonlinear analysis and optimization,a novel implementation of adjoint vector sensitivity analysis along with super element condensation is introduced to address numerical instability *** degrees of freedom of weak regions are condensed so that their influences are excluded from the iterative Newton-Raphson(NR)*** examples are presented to validate the efficiency and robustness of the proposed *** effects of joint load constraints and geometrical nonlinearity are highlighted by comparing numerical optimization results.

关键词： Geometrical nonlinearity Joint load constraint Sensitivity analysis Super element condensation Topology optimization

Stiffeners layout design of thin-walled structures with constraints on multi-fastener joint loads

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Chinese Journal of Aeronautics 2017年第4期30卷 1441-1450页

作者： Jie HOU Jihong ZHU Fei HE weihong zhang Wenjie GUO Engineering Simulation & Aerospace Computing The Key Laboratory of Contemporary Design and Integrated Manufacturing Technology Northwestern Polytechnieal University Xi'an 710072 China

The purpose of this paper is to present an extended topology optimization method for the stiffeners layout design of aircraft assembled structures. Multi-fastener joint loads and manufacturing constraints are considered simultaneously. On one hand, the joint loads are calculated and constrained within a limited value to avoid the failure of fasteners. On the other hand, the manufacturing constraints of the material distribution in the machining directions of stiffeners are implemented by an improved piecewise interpolation based on a beveled cut-surface. It is proven that the objective function is strictly continuous and differentiable with respect to the piecewise interpolation. The effects of the extended method with two different constraints are highlighted by typical numerical examples. Compared with the standard topology optimization, the final designs have clearly shown the layout of stiffeners and the joint loads have been perfectly constrained to a satisfying level.

关键词： Joint load constraint Manufacturing constraint Stiffeners Thin-walled structures Topology optimization

Shape optimization of 3D curved slots and its application to the squirrel-cage elastic support design

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Science China(Physics,Mechanics & Astronomy) 2010年第10期53卷 1895-1900页

作者： WANG Dan zhang weihong WANG ZhenPei ZHU JiHong Engineering Simulation and Aerospace Computing The Key Laboratory of Contemporary Design&Integrated Manufacturing TechnologyNorthwestern Polytechnical UniversityXi’an 710072China

The squirrel-cage elastic support is one of the most important components of an aero-engine rotor system.A proper structural design will favor the static and dynamic performances of the *** view of the deficiency of the current shape optimization techniques,a new mapping approach is proposed to define shape design variables based on the parametric equations of 3D curves and *** is then applied for the slot shape optimization of a squirrel-cage elastic *** this end,an automatic design procedure that integrates the Genetic Algorithm (GA) is developed to solve the *** typical examples with different shape constraints are *** results provide reasonable optimum designs for the improvement of stiffness and strength of the squirrel-cage elastic support.

关键词： shape optimization mapping design approach stress concentration spindly slot squirrel-cage elastic support

Using strain energy-based prediction of effective elastic properties in topology optimization of material microstructures

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Acta Mechanica Sinica 2007年第1期23卷 77-89页

作者： weihong zhang Gaoming Dai Fengwen Wang Shiping Sun Hicham Bassir Institute of Mechatronic Engineering Northwestern Polytechnical University Xi'an 710072 China FEMTO-ST Department of LMARC UMR--CNRS 6174 25000 Besancon France

An alternative strain energy method is proposed for the prediction of effective elastic properties of orthotropic materials in this paper. The method is implemented in the topology optimization procedure to design cellular solids. A comparative study is made between the strain energy method and the well-known homogenization method. Numerical results show that both methods agree well in the numerical prediction and sensitivity analysis of effective elastic tensor when homogeneous boundary conditions are properly specified. Two dimensional and three dimensional microstructures are optimized for maximum stiffness designs by combining the proposed method with the dual optimization algorithm of convex programming. Satisfactory results are obtained for a variety of design cases.

关键词： Cellular solids Material design Homogenization method Strain energy Topology optimization

Fiber Bundle Topology Optimization for Surface Flows

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 236-264页

作者： Yongbo Deng weihong zhang Jihong Zhu Yingjie Xu Jan G Korvink State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi’an 710072China Institute of Microstructure Technology(IMT) Karlsruhe Institute of Technology(KIT)Hermann-von-Helmholtzplatz 176344 Eggenstein-LeopoldshafenGermany

This paper presents a topology optimization approach for the surface flows on variable design *** this approach,the matching between the pattern of a surface flow and the 2-manifold used to define the pattern can be optimized,where the 2-manifold is implicitly defined on another fixed 2-manifold named as the base *** fiber bundle topology optimization approach is developed based on the description of the topological structure of the surface flow by using the differential geometry concept of the fiber *** material distribution method is used to achieve the evolution of the pattern of the surface *** evolution of the implicit 2-manifold is realized via a homeomorphous *** design variable of the pattern of the surface flow and that of the implicit 2-manifold are regularized by two sequentially implemented surface-PDE *** two surface-PDE filters are coupled,because they are defined on the implicit 2-manifold and base manifold,*** surface Navier-Stokes equations,defined on the implicit 2-manifold,are used to describe the surface *** fiber bundle topology optimization problem is analyzed using the continuous adjoint method implemented on the first-order Sobolev *** numerical examples have been provided to demonstrate this approach,where the combination of the viscous dissipation and pressure drop is used as the design objective.

关键词： Fiber bundle Topology optimization 2-manifold Surface flow Material distribution method Porous medium model

Information Technology and the Construction of New English Teaching Model in China

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学术界 2015年第2期 298-302页

作者： zhang weihong Lin Lilan Department of Basic Teaching & Experiment HefeiUniversity Hefei Anhui 230013 School ofForeignStudies Anhui Jianzhu University Hefei Anhui 230601

The role that information technology plays in foreign language teaching is no longer confined to assisting teachers to impart knowledge. This paper aims at construction of new English teaching model based on information technology. The author adopted ethnographic research to observe 8 classes and the findings of this study suggest that until frontline teachers deepen their understanding of information technology and change their philosophy of teaching can a successful implementation of the new teaching model be ensured.

关键词：信息技术教学模式英语中国外语教学教学理念人种学教师

Compressive behavior and energy absorption of polymeric lattice structures made by additive manufacturing

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Frontiers of Mechanical Engineering 2020年第2期15卷 319-327页

作者： Sheng WANG Jun WANG Yingjie XU weihong zhang Jihong ZHU State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi’an 710072China Intelligent Materials and Structures Unmanned System Research InstituteNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Engineering Laboratory of Aerospace Structure Design and Application Northwestern Polytechnical UniversityXi’an 710072China

Lattice structures have numerous outstanding characteristics,such as light weight,high strength,excellent shock resistance,and highly efficient heat *** this work,by combining experimental and numerical methods,we investigate the compressive behavior and energy absorption of lattices made through the stereolithography apparatus *** types of lattice structures are considered:(i)Uniform bodycentered-cubic(U-BCC);(ii)graded body-centered-cubic(G-BCC);(iii)uniform body-centered-cubic with z-axis reinforcement(U-BCCz);and(iv)graded body-centeredcubic with z-axis reinforcement(G-BCCz).We conduct compressive tests on these four lattices and numerically simulate the compression process through the finite element *** results show that BCCz has higher modulus and strength than *** addition,uniform lattices show better energy absorption capabilities at small compression distances,while graded lattices absorb more energy at large compression *** good correlation between the simulation results and the experimental phenomena demonstrates the validity and accuracy of the present investigation method.

关键词： lattice structure polymer compressive behavior additive manufacturing simulation

Improving ModeⅡdelamination resistance of curved CFRP laminates by a Pre-Hole Z-pinning(PHZ)process

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Chinese Journal of Aeronautics 2023年第2期36卷 316-324页

作者： Xuebei TENG Yingjie XU weihong zhang Xinyu HUI Weiwei LIU Chengyan MA State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi'an 710072China Shaanxi Engineering Laboratory of Aerospace Structure Design and Application Northwestern Polytechnical UniversityXi'an 710072China Shandong Institute of Non-Metallic Materials Jinan 250031China

This paper presents an experimental investigation of the ModeⅡdelamination resistance of curved CFRP laminates reinforced with Z-pins.A Pre-Hole Z-pinning(PHZ)process is developed to reduce the in-plane damage of the Z-pinned *** microstructural observation of the Z-pinned laminate specimens indicates that the PHZ process can effectively decrease the defects including the Z-pin offset angle and the area of eyelet *** influences of the volume fraction and diameter of Z-pin on the fracture toughness and the delamination crack growth rate of the specimens under End Notch Flexure(ENF)loading are then determined *** test results show that Z-pin increases the interlayer stiffness of the *** delamination crack growth rate is reduced with the increase of Z-pin diameter and volume fraction,and a reduction up to 40%is achieved compared with the specimens without ***,the ModeⅡfracture toughness is significantly improved with the increase of Z-pin volume *** Z-pin volume fraction increases by 1%,the achieved fracture toughness is about 200%higher compared to the unpinned laminates.

关键词： CFRP Curved laminates Delamination resistance Fracture toughness ModeⅡ Z-pins