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China Foundry 2024年第1期21卷 11-19页

作者： Wen-ning Liu Wei Zhang Peng-yue Wang Yi-xian Liu Xiang-yi Jiao Ao-xiang Wan Cheng-gang Wang Guo-dong Tong Shou-mei Xiong School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Tsinghua UniversityBeijing 100084Beijing China faw group Co. Ltd.Changchun 130013China China faw Foundry Co. Ltd.Changchun 130013China

The effect of slow shot speed on externally solidified crystal(ESC),porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy was investigated by optical microscopy(OM),scanning electron microscopy(SEM)and laboratory computed tomography(CT).Results showed that the newly developed AlSi9MnMoV alloy exhibited improved mechanical properties when compared to the AlSi10MnMg *** AlSi9MnMoV alloy,which was designed with trace multicomponent additions,displays a notable grain refining effect in comparison to the AlSi10MnMg *** elements Ti,Zr,V,Nb,B promote heterogeneous nucleation and reduce the grain size of primaryα-*** a lower slow shot speed,the large ESCs are easier to form and gather,developing into the dendrite net and *** an increase in slow shot speed,the size and number of ESCs and porosities significantly *** addition,the distribution of ESCs is more dispersed and the net-shrinkage *** tensile property is greatly improved by adopting a higher slow shot *** ultimate tensile strength is enhanced from 260.31 MPa to 290.31 MPa(increased by 11.52%),and the elongation is enhanced from 3.72%to 6.34%(increased by 70.52%).

关键词： hypoeutectic Al-Si alloy high pressure die casting porosity externally solidified crystal tensile property

Structural Properties of Ions and Polyelectrolytes in Aqueous Solutions under External Electric Fields:The Sign Effect

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Chinese Journal of Polymer Science 2024年第9期42卷 1341-1352,I0007页

作者： Cheng-Jiang Lin Jun-Jun Wang Yuan Jiang Shu-Li Chen Hong-Fei Li Wen-Han Zhao Qing-Rong Huang Chang-Ru Rong Xiao-Zheng Duan State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China National Key Laboratory of Advanced Vehicle Integration and Control China FAW Group Co.Ltd.Changchun130013China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200438China Department of Food Science Rutgers University65 Dudley RoadNew BrunswickNew Jersey08901USA

We utilize molecular dynamics simulations to investigate the microstructures of ions and polyelectrolytes in aqueous solutions under external electric *** focusing on the multi-body interactions between ionic components and H_(2)O molecules,as well as their responses to the external electric fields,we clarify several nontrivial molecular features of the ionic and polyelectrolyte solutions,such as the solvations of cations and anions,clustering of the ions,and dispersions/aggregations of polyelectrolyte chains,as well as the corresponding responses of H_(2)O molecules in these *** simulations illustrate the variations in structures of ionic solutions caused by reversing the charge sign of the ions,and elucidate the disparity in structures between anionic and cationic polyelectrolyte solutions in the presence of the external electric *** work clarifies the mechanism for the alternations in complex multi-body interactions in aqueous solutions caused by the application electric field,which can contribute to the fundamental understanding of the physical and chemical natures of ion-containing and charged polymeric systems.

关键词： Polyelectrolyte Ions Aqueous solutions External electric fields Asymmetric dipole

Evaluation of forming limit in viscous pressure forming of automotive aluminum alloy 6k21-T4 sheet

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中国有色金属学会会刊：英文版 2007年第6期17卷 1169-1174页

作者：王忠金李毅刘建光张义和 School of Materials Science and Engineering Harbin Institute of Technology Research and Development Center China FAW Group Corporation

A ductile fracture criterion is introduced into numerical simulation to predict viscous pressure forming limit of the automotive body aluminum alloy 6k21-T4. The material constant in the ductile fracture criterion is determined by the combination of the viscous pressure bulging (VPB) test with numerical simulation. VPB tests of the aluminum alloy sheet are carried out by using various elliptical dies with different ratios of major axis to minor axis(β), and the bugling processes are simulated by the aid of the finite element method software LS-DYNA3D. On the basis of the stress and strain calculated from numerical simulations, the forming limits of bulging specimens obtained are predicted by the ductile fracture criterion, and compared with experimental results. The fracture initiation site and the minimal thickness predicted by the ductile fracture criterion are in good agreement with the experimental results.

关键词：铝合金薄片延展断裂有限远元分析机械性质

Performance Development Target Setting of Passenger Car Diesel Engine

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Chinese Journal of Mechanical Engineering 2013年第3期26卷 512-517页

作者： ZHENG Guangyong YU Xiumin LIU Jiangwei SONG Tao LI Wenxiang State Key Lab of Automotive Dynamic Simulation Jilin University Research and Development Center FAW Group Corporation

Setting engine emission targets to meet diesel car requirements is particularly important in engine performance development phase. Many researches are focused on associating vehicle performance with engine targets, but most work is done by testing, which is time and cost consuming, furthermore, the relationship of vehicle and engine will change when either engine or vehicle changes. A GT-Drive model to simulate New European Driving Cycle (NEDC) for passenger car is developed and calibrated by testing data, model precision is controlled within 5%. Time distribution of engine operating conditions when car running NEDC cycle has been analyzed, 10 critical major engine operating points are summarized according to running time proportion. Emission of NOx and smoke control regions containing these 10 points for target engine are set. Vehicle emissions are simulated and evaluated during engine development after engine performance test data are got, and engine combustion system layout and calibration are adjusted until vehicle targets are met. Vehicle is tested in chassis dynamometer finally, the testing results show a good agreement with the simulated results with an error of less than 5%, which proves that the emission value exchange of vehicle and engine is reliable. Performance target decomposition method for passenger car diesel presented can greatly shorten the development cycle and save costs.

关键词： passenger car diesel engine emission target New European Driving Cycle simulation analysis

Autotuning algorithm of particle swarm PID parameter based on D-Tent chaotic model

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Journal of Systems Engineering and Electronics 2013年第5期24卷 828-837页

作者： Min Zhu Chunling Yang Weiliang Li School of Electrical Engineering and Automation Harbin Institute of Technology China faw group Corporation R&D Center

An improved particle swarm algorithm based on the D-Tent chaotic model is put forward aiming at the standard particle swarm algorithm. The convergence rate of the late of proposed algorithm is improved by revising the inertia weight of global optimal particles and the introduction of D-Tent chaotic sequence. Through the test of typical function and the autotuning test of proportionalintegral-derivative （PID） parameter, finally a simulation is made to the servo control system of a permanent magnet synchronous motor （PMSM） under double-loop control of rotating speed and current by utilizing the chaotic particle swarm algorithm. Studies show that the proposed algorithm can reduce the iterative times and improve the convergence rate under the condition that the global optimal solution can be got.

关键词： D-Tent particle swarm proportional-integral- derivative (PID) parameter optimization.

Vibration Isolation Performance Research of Commercial Truck’s Cab Suspension System Based on Road Load Data

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Vibration Isolation Performance Research of Commercial Truck...

Technology Development Analysis on Low Carbon for Power of Heavy-Duty Commercial Vehicle

2014中国汽车工程学会年会

作者： Yan Xin Jiang Di Wang Zhongxiao Guo Maolin China faw group Corporation R＆D Center

ISBN: (纸本)9783662450420

Based on road load data of commercial truck’s cab suspension system,extreme value and standard deviation of acceleration signals are statistically *** then pseudo-damage analysis is done to get the damage attenuation level of the shock *** to the theory of shock absorber vibration isolation,amplitude frequency response characteristics of the cab suspension system are *** of the study is to find a way to evaluate the performance of commercial truck’s cab suspension *** is very useful to guide the forward design of cab suspension system from the perspective of passenger comfort and component fatigue life so that it can provide data support and improvement suggestions for the development of commercial truck cab suspension system.

关键词： road load data pseudo-damage vibration isolation performance

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Automotive Innovation 2019年第1期2卷 64-70页

作者： Jiangwei Liu Jun Li Yongjun Wang Dalu Dong Yansheng Yin Huayu Jin Shijie Sun Huili Dou Yanbo Shi Lei Fu Fei Ge China faw group Corporation Limited Changchun 130000China Tsinghua University Beijing 100084China

Commercial vehicle industry worldwide is facing challenges from environmental pressures,stringent limits of CO_(2) emission,governmental regulations as well as ever-increased customer *** paper analyzes the above-mentioned challenges,especially in China,including the potential improvement to increase the brake thermal efficiency(BTE),with five levels of BTE proposed,ranging from current 45 to 60%in future,corresponding to China fuel consumption regulation(CFCR)in different *** authors also proposed the technology roadmaps to meet the upcoming CFCR3 and CFCR4;finally,the authors draw the conclusions to conform with ever-stringent regulation in China.

关键词： Heavy-duty diesel engine(HDDE) Low carbon Fuel consumption

Accuracy Analysis and Design of A3 Parallel Spindle Head

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Chinese Journal of Mechanical Engineering 2016年第2期29卷 239-249页

作者： NI Yanbing ZHANG Biao SUN Yupeng ZHANG Yuan School of Mechanical Engineering Tianjin University Tianjin 300072 China China faw group Corporation R&D Center Changchun 130000 China

As functional components of machine tools, parallel mechanisms are widely used in high efficiency machining of aviation components, and accuracy is one of the critical technical indexes. Lots of researchers have focused on the accuracy problem of parallel mechanisms, but in terms of controlling the errors and improving the accuracy in the stage of design and manufacturing, further efforts are required. Aiming at the accuracy design of a 3-DOF parallel spindle head（A3 head）, its error model, sensitivity analysis and tolerance allocation are investigated. Based on the inverse kinematic analysis, the error model of A3 head is established by using the first-order perturbation theory and vector chain method. According to the mapping property of motion and constraint Jacobian matrix, the compensatable and uncompensatable error sources which affect the accuracy in the end-effector are separated. Furthermore, sensitivity analysis is performed on the uncompensatable error sources. The sensitivity probabilistic model is established and the global sensitivity index is proposed to analyze the influence of the uncompensatable error sources on the accuracy in the end-effector of the mechanism. The results show that orientation error sources have bigger effect on the accuracy in the end-effector. Based upon the sensitivity analysis results, the tolerance design is converted into the issue of nonlinearly constrained optimization with the manufacturing cost minimum being the optimization objective. By utilizing the genetic algorithm, the allocation of the tolerances on each component is finally determined. According to the tolerance allocation results, the tolerance ranges of ten kinds of geometric error sources are obtained. These research achievements can provide fundamental guidelines for component manufacturing and assembly of this kind of parallel mechanisms.

关键词： A3 head error model sensitivity analysis tolerance allocation

Modeling of LiFePO4 battery open circuit voltage hysteresis based on recursive discrete Preisach model

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Chinese Physics B 2017年第12期26卷 552-559页

作者：孙维毅闵海涛郭冬妮于远彬 State Key Laboratory of Automotive Simulation and Control Jilin University Changchun 130022 China China faw group Corporation R & D Center Changchun 130011 China

This paper focuses on the modeling of LiFePO4 battery open circuit voltage （OCV） hysteresis. There exists obvious hysteresis in LiFePO4 battery OCV, which makes it complicated to model the LiFePO4 battery. In this paper, the recursive discrete Preisach model （RDPM） is applied to the modeling of LiFePO4 battery OCV hysteresis. The theory of RDPM is illustrated in detail and the RDPM on LiFePO4 battery OCV hysteresis modeling is verified in experiment. The robust of RDPM under different working conditions are also demonstrated in simulation and experiment. The simulation and experimental results show that the proposed method can significantly improve the accuracy of LiFePO4 battery OCV hysteresis modeling when the battery OCV characteristic changes, which conduces to the online state estimation of LiFePO4 battery.

关键词： hysteresis lithium-ion batteries modeling

Simulation and Validation of Engine Valvetrains System Dynamics

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Simulation and Validation of Engine Valvetrains System Dynam...