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Frontiers of Structural and Civil Engineering 2023年第9期17卷 1428-1441页

作者： Jia’ao YU Zhenzhong SHEN Zhangxin HUANG Haoxuan LI State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210024China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210024China

High-rise intake towers in high-intensity seismic areas are prone to structural safety problems under vibration.Therefore,effective and low-cost anti-seismic engineering measures must be designed for protection.An intake tower in northwest China was considered the research object,and its natural vibration characteristics and dynamic response were first analyzed using the mode decomposition response spectrum method based on a three-dimensional finite element model.The non-dominated sorting genetic algorithm-II(NSGA-II)was adopted to optimize the anti-seismic scheme combination by comprehensively considering the dynamic tower response and variable project cost.Finally,the rationality of the original intake tower antiseismic design scheme was evaluated according to the obtained optimal solution set,and recommendations for improvement were proposed.The method adopted in this study may provide significant references for designing anti-seismic measures for high-rise structures such as intake towers located in high-intensity earthquake areas.

关键词： intake tower NSGA-II mode decomposition response spectrum method anti-seismic engineering measures Optimization design variable project cost

Optimization design of airfoils under atmospheric icing conditions for UAV

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Chinese Journal of Aeronautics 2022年第4期35卷 118-133页

作者： Haoran LI Yufei ZHANG Haixin CHEN School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

Natural ice accretion on the lifting surface of an aircraft is detrimental to its aerodynamic performance, as it changes the effective streamlined body. The main focus of this work considers the Optimization design of airfoils under atmospheric icing conditions for the Unmanned Aerial Vehicle(UAV). The ice formation process is simulated by the Eulerian approach and the three-dimensional Myers model. A three-equation turbulence model is implemented to accurately predict the stall performance of the iced airfoil. In recognition of the real atmospheric variability in the icing parameters, the medium volume diameter of supercooled water droplets is treated as an uncertainty with an assumed probability density function. A technique of polynomial chaos expansion is used to propagate the input uncertainty through the deterministic system. The numerical results show that the multipoint/multiobjective optimization strategy can efficiently improve both the ice tolerance and the cruise performance of an airfoil. The reason for the focus on robust optimization is that the ice angle of the optimized airfoil becomes less critical to the incoming flow.The optimized airfoils are applied to a UAV platform, in which the performance improvement and the relevant key flow feature are both preserved.

关键词： Aircraft icing Ice-accretion Ice-tolerant airfoil Optimization design Separated flow UAV

Optimization design of two-stage amplification micro-drive system without additional motion based on particle swarm optimization algorithm

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Visual Computing for Industry,Biomedicine,and Art 2022年第1期5卷 340-351页

作者： Manzhi Yang Kaiyang Wei Chuanwei Zhang Dandan Liu Yizhi Yang Feiyan Han Shuanfeng Zhao School of Mechanical Engineering Xi’an University of Science and TechnologyXi’an 710054China Department of Mechanical and Aerospace Engineering Brunel University LondonUxbridge 361199UK School of Humanities and Foreign Languages Xi’an University of Science and TechnologyXi’an 710054China

With the increasing requirements of precision mechanical systems in electronic packaging,ultra-precision machining,biomedicine and other high-tech fields,it is necessary to study a precision two-stage amplification micro-drive system that can safely provide high precision and a large amplification ratio.In view of the disadvantages of the current two-stage amplification and micro-drive system,such as poor security,low motion accuracy and limited amplification ratio,an Optimization design of a precise symmetrical two-stage amplification micro-drive system was completed in this study,and its related performance was studied.Based on the guiding principle of the flexure hinge,a two-stage amplification micro-drive mechanism with no parasitic motion or non-motion direction force was designed.In addition,the structure Optimization design of the mechanism was completed using the particle swarm optimization algorithm,which increased the amplification ratio of the mechanism from 5 to 18 times.A precise symmetrical two-stage amplification system was designed using a piezoelectric ceramic actuator and two-stage amplification micro-drive mechanism as the micro-driver and actuator,respectively.The driving,strength,and motion performances of the system were subsequently studied.The results showed that the driving linearity of the system was high,the strength satisfied the design requirements,the motion amplification ratio was high and the motion accuracy was high(relative error was 5.31%).The research in this study can promote the optimization of micro-drive systems.

关键词： Particle swarm optimization Micro-drive mechanism Two-stage amplification Optimization design Performance of guidance

Optimization design containing dimension and buffer parameters of landing legs for reusable landing vehicle

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Chinese Journal of Aeronautics 2022年第3期35卷 234-249页

作者： Bo LEI Ming ZHANG Hanyu LIN Hong NIE Key Laboratory of Fundamental Science for National Defense-Advanced design Technology of Flight Vehicle Nanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of Mechanics and Control of Mechanical Structure Nanjing University of Aeronautics and AstronauticsNanjing 210016China

For the landing legs with single air chamber in the buffer structure of the reusable landing vehicle,the geometric topological models and the dynamic model associated with the hard points of the landing legs are established.The geometric constraint relationship in the design of the landing legs is also obtained.The whole vehicle dropping test is conducted,and the test results agree well with that of the simulation model,which validates the dynamic model.Based on the verified model,the effect of hard point positions on the performance of the landing system is analyzed.The multidisciplinary collaborative optimization algorithm and archive-based micro genetic algorithm(CO-AMGA)are used to optimize the design parameters that contain the hard points and the damper.Compared with artificial iteration,the maximum landing impact acceleration response of the vehicle and the buffer struct maximum force are reduced by 30.70%and 14.51%respectively,and the maximum length of retractable pillar decreases by 8.54%while the design margin increases by 69.11%.The proposed optimization method is efficient and can greatly facilitate the design of landing legs.

关键词： Dynamics Impact test Landing system Optimization design Reusable landing vehicle

A Hybrid Level Set Optimization design Method of Functionally Graded Cellular Structures Considering Connectivity

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Computers, Materials & Continua 2024年第4期79卷 1-18页

作者： Yan Dong Kang Zhao Liang Gao Hao Li The State Key Lab of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China Institute of Systems Engineering China Academy of Engineering PhysicsMianyang621900China

With the continuous advancement in topology optimization and additive manufacturing(AM)technology,the capability to fabricate functionally graded materials and intricate cellular structures with spatially varying microstructures has grown significantly.However,a critical challenge is encountered in the design of these structures–the absence of robust interface connections between adjacent microstructures,potentially resulting in diminished efficiency or macroscopic failure.A Hybrid Level Set Method(HLSM)is proposed,specifically designed to enhance connectivity among non-uniform microstructures,contributing to the design of functionally graded cellular structures.The HLSM introduces a pioneering algorithm for effectively blending heterogeneous microstructure interfaces.Initially,an interpolation algorithm is presented to construct transition microstructures seamlessly connected on both sides.Subsequently,the algorithm enables the morphing of non-uniform unit cells to seamlessly adapt to interconnected adjacent microstructures.The method,seamlessly integrated into a multi-scale topology optimization framework using the level set method,exhibits its efficacy through numerical examples,showcasing its prowess in optimizing 2D and 3D functionally graded materials(FGM)and multi-scale topology optimization.In essence,the pressing issue of interface connections in complex structure design is not only addressed but also a robust methodology is introduced,substantiated by numerical evidence,advancing optimization capabilities in the realm of functionally graded materials and cellular structures.

关键词： Hybrid level set method functionally graded cellular structure connectivity interpolated transition Optimization design

Recent advances in cobalt phosphide-based materials for electrocatalytic water splitting:From catalytic mechanism and synthesis method to Optimization design

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Nano Materials Science 2024年第2期6卷 139-173页

作者： Rongrong Deng Mengwei Guo Chaowu Wang Qibo Zhang Key Laboratory of Ionic Liquids Metallurgy Faculty of Metallurgical and Energy EngineeringKunming University of Science and TechnologyKunming650093PR China State Key Laboratory of Complex Nonferrous Metal Resources Cleaning Utilization in Yunnan Province Kunming650093PR China

Electrochemical water splitting has long been considered an effective energy conversion technology for trans-ferring intermittent renewable electricity into hydrogen fuel,and the exploration of cost-effective and high-performance electrocatalysts is crucial in making electrolyzed water technology commercially viable.Cobalt phosphide(Co-P)has emerged as a catalyst of high potential owing to its high catalytic activity and durability in water splitting.This paper systematically reviews the latest advances in the development of Co-P-based materials for use in water splitting.The essential effects of P in enhancing the catalytic performance of the hydrogen evolution reaction and oxygen evolution reaction are first outlined.Then,versatile synthesis techniques for Co-P electrocatalysts are summarized,followed by advanced strategies to enhance the electrocatalytic performance of Co-P materials,including heteroatom doping,composite construction,integration with well-conductive sub-strates,and structure control from the viewpoint of experiment.Along with these optimization strategies,the understanding of the inherent mechanism of enhanced catalytic performance is also discussed.Finally,some existing challenges in the development of highly active and stable Co-P-based materials are clarified,and pro-spective directions for prompting the wide commercialization of water electrolysis technology are proposed.

关键词： Co-P electrocatalysts Water splitting Hydrogen production Catalytic mechanism Synthesis technique Optimization design

Comprehensive Optimization design of aerodynamic and electromagnetic scattering characteristics of serpentine nozzle

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Chinese Journal of Aeronautics 2021年第3期34卷 118-128页

作者： Yubo HE Qingzhen YANG Xiang GAO School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China

Comprehensive Optimization design of serpentine nozzle with trapezoidal outlet was studied to improve its aerodynamic and electromagnetic scattering performance.Serpentine nozzles with different center offsets and different ratios of the bases of the trapezoidal outlet were generated based on curvature control regulation.Computational Fluid Dynamics(CFD)simulations have been conducted to obtain the flow field in the nozzle,and Forward-Backward Iterative Physical Optics(FBIPO)method was applied to study the electromagnetic scattering characteristics of the nozzle.Guarantee Convergence Particle Swarm optimization(GCPSO)algorithm based on Radial Basis Function(RBF)neural network was used to optimize the geometry of the nozzle in consideration of its aerodynamic and electromagnetic scattering characteristics.The results show that the GCPSO method based on RBF can be used to optimize the aerodynamic characteristics of the internal flow and the scattering characteristics of the cavity of the serpentine nozzle with irregular outlet.The optimized model has a higher center offset and a lower ratio of the bases of the trapezoidal outlet after optimization compared to the original model.The optimized model leads to a slight change in aerodynamic performance,with a total pressure recovery coefficient increase of 0.31%and a discharge coefficient increase of 0.41%.In addition,the Radar Cross Section(RCS)decreases also by around 83.33%and the overall performance is significantly improved,with a decrease of the optimized objective function by around 38.74%.

关键词： Forward-Backward Iterative Physical Optics(FBIPO) Guarantee Convergence Particle Swarm optimization(GCPSO) Nozzle design Optimization design Radar Cross Section(RCS) Serpentine nozzle

Optimization design of multiphase pump impeller based on combined genetic algorithm and boundary vortex flux diagnosis

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Journal of Hydrodynamics 2017年第6期29卷 1023-1034页

作者：张金亚蔡淑杰李泳江周鑫张永学 College of Mechanical and Transportation Engineering Beijing Key Laboratory of Process Fluid Filtration and SeparationChina University of PetroleumBeijing 102249China

A novel Optimization design method for the multiphase pump impeller is proposed through combining the quasi-3D hydraulic design（Q3DHD）, the boundary vortex flux（BVF） diagnosis, and the genetic algorithm（GA）. The BVF diagnosis based on the Q3DHD is used to evaluate the objection function. Numerical simulations and hydraulic performance tests are carried out to compare the impeller designed only by the Q3DHD method and that optimized by the presented method. The comparisons of both the flow fields simulated under the same condition show that（1） the pressure distribution in the optimized impeller is more reasonable and the gas-liquid separation is more efficiently inhibited,（2） the scales of the gas pocket and the vortex decrease remarkably for the optimized impeller,（3） the unevenness of the BVF distributions near the shroud of the original impeller is effectively eliminated in the optimized impeller. The experimental results show that the differential pressure and the maximum efficiency of the optimized impeller are increased by 4% and 2.5%, respectively. Overall, the study indicates that the Optimization design method proposed in this paper is feasible.

关键词： Optimization design multiphase pump genetic algorithm boundary vortex flux quasi-3D hydraulic design （Q3DHD）

Optimization design and test of rice plug seedling transplanting mechanism of planetary gear train with incomplete eccentric circular gear and non-circular gears

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International Journal of Agricultural and Biological Engineering 2017年第6期10卷 43-55页

作者： Ye Bingliang Yi Weiming Yu Gaohong Gao Yang Zhao Xiong Faculty of Mechanical Engineering and Automation Zhejiang Sci-Tech UniversityHangzhou 310018China Zhejiang Province Key Laboratory of Transplanting Equipment and Technology Hangzhou 310018China

In order to solve the problem of the high-speed mechanized transplanting of rice plug seedlings,the design requirements of transplanting mechanism for rice plug seedlings were analyzed and a kind of rice plug seedling transplanting mechanism of planetary gear train based on the drive with incomplete eccentric circular gear and non-circular gears was designed innovatively.The laboratory kinematics was examined.The working principle of the transplanting mechanism for rice plug seedlings was studied,kinematics analysis of the transplanting mechanism was carried out and its kinematic model was set up.A human-computer interaction optimization method was used to optimize the parameters of the transplanting mechanism.The computer aided analysis and optimization software of the transplanting mechanism based on Visual Basic 6.0 was developed.Through analyzing the influence of design variables on the optimization objectives of the transplanting mechanism,a set of parameters of the transplanting mechanism which meet the requirements of transplanting trajectory and posture for transplanting rice seedlings were obtained by means of human-computer interaction.The structure of the transplanting mechanism was designed according to this set of parameters,and its virtual prototype and physical prototype were set up and manufactured,respectively.The kinematic simulation test and high-speed photography kinematic test of the transplanting mechanism were conducted to obtain its kinematic performances,such as transplanting trajectory and posture.The results of bench test,simulation analysis and theoretical analysis were almost in agreement,which verified the correctness of the theoretical model and design results of the transplanting mechanism,indicating that the optimized transplanting mechanism can satisfy the requirements of transplanting rice seedlings and be applied in the rice plug seedling transplanter.

关键词： plug seedling transplanting mechanism incomplete eccentric circular gear non-circular gear planetary gear train Optimization design

Performance experiment and numerical prediction on the Optimization design of the micro-sized water turbine for the hose reel irrigator

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International Journal of Agricultural and Biological Engineering 2018年第5期11卷 108-115页

作者： Lingdi Tang Shouqi Yuan Yue Tang Haofang Yan Research Center of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenJiang 212013China

In order to significantly improve the efficiency of driving water turbine used in hose reel irrigator,a new water turbine structure was proposed by the method of performance test and numerical calculation.The internal flow characteristics of original water turbine were analyzed,and it was found that unreasonable design of main flow passage components such as inlet,outlet and runner could not effectively translated pressure energy of upper stream into impact kinetic energy of blade,and gave rise to low energy conversion efficiency of water turbine.The inadequate internal flow and uneven pressure distribution were also not conducive to energy conversion efficiency.Then a new structure of water turbine structure was presented,in which the inlet has a tangential nozzle jet and the outlet is in axial direction.The computational analysis showed that the nozzle jet at the inlet of the new water turbine runner,which makes jet flow mainly concentrate in the impacted blade passage,can reduce the loss of flow kinetic energy.The axial outflow increases the distance of inflow in the runner,which is more conducive to the runner blades work.Performance experiments on both original and new water turbines showed that the highest efficiency of the new turbine is almost 20 percentages higher than that of the original turbine,and the new turbine is nearly triple output power over the original turbine.The internal flow characteristic analysis and the performance experiment were conducted to assess the feasibility of the replacement of the original water turbine by the new water turbine.

关键词： micro-sized water turbine hose reel irrigator Optimization design experimental study numerical analysis