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Applied Mathematics and Mechanics(English Edition) 2018年第9期39卷 1277-1294页

作者： Zhou YU Hongda ZHANG Taohong YE Minming ZHU Department of Thermal Science and Energy Engineering University of Science and Technology of China Shenyang Engine Research Institute Aero Engine (Group) Corporation of China

A sub-grid scale(SGS) combustion model, which combines the artificial thickened flame(ATF) model with the flamelet generated manifold(FGM) tabulation method, is proposed. Based on the analysis of laminar flame structures, two self-contained flame sensors are used to track the diffusion and reaction processes with different spatial scales in the flame front, respectively. The dynamic formulation for the proposed SGS combustion model is also performed. Large eddy simulations(LESs) of Bunsen flame F3 are used to evaluate the different SGS combustion models. The results show that the proposed SGS model has the ability in predicting the distributions of temperature and velocity reasonably, while the predictions for the distributions of some species need further improvement. The snapshots of instantaneous normalized progress variables reveal that the flame is more remarkably and severely wrinkled at the flame tip for flame *** satisfactory results obtained by the dynamic model indicate that it can preserve the premixed flame propagation characteristics better.

关键词： large eddy simulation(LES) artificial thickened flame model tabulation dynamic modeling flame sensor

Complete geometric nonlinear formulation for rigid-flexible coupling dynamics

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Journal of Central South University 2009年第1期16卷 119-124页

作者：刘铸永洪嘉振刘锦阳 Department of Engineering Mechanics Shanghai Jiao Tong University

A complete geometric nonlinear formulation for rigid-flexible coupling dynamics of a flexible beam undergoing large overall motion was proposed based on virtual work principle, in which all the high-order terms related to coupling deformation were included in dynamic equations. Simulation examples of the flexible beam with prescribed rotation and free rotation were investigated. Numerical results show that the use of the first-order approximation coupling (FOAC) model may lead to a significant error when the flexible beam experiences large deformation or large deformation velocity. However, the correct solutions can always be obtained by using the present complete model. The difference in essence between this model and the FOAC model is revealed. These coupling high-order terms, which are ignored in FOAC model, have a remarkable effect on the dynamic behavior of the flexible body. Therefore, these terms should be included for the rigid-flexible dynamic modeling and analysis of flexible body undergoing motions with high speed.

关键词： flexible beam rigid-flexible coupling dynamic modeling numerical simulation

modeling and controlling of a flexible hydraulic manipulator

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Journal of Central South University of Technology 2005年第5期12卷 578-583页

作者：李光吴敏 Department of Mechanical Engineering Zhuzhou Institute of Technology Zhuzhou 412008 ChinaSchool of Information Science and Engineering Central South University Chansha 410083 China School of Information Science and Engineering Central South University Chansha 410083 China

A mathematical model was developed combining the dynamics of an Euler-Bernoulli beam, described by the assumed-mode method and hydraulic circuit dynamics. Only one matrix, termed drive Jacobian, was needed in the modeling of interaction between hydraulic circuit and flexible manipulator mechanism. Furthermore, a new robust controller based on mentioned above dynamic model was also considered to regulate both flexural vibrations and rigid body motion. The proposed controller combined sliding mode and backstepping techniques to deal with the nonlinear system with uncertainties. The sliding mode control was used to achieve an asymptotic joint angle and vibration regulation by providing a virtual force while the backstepping technique was used to regulate the spool position of a hydraulic valve to provide the required control force. Simulation results are presented to show the stabilizing effect and robustness of this control strategy.

关键词： dynamic modeling flexible manipulator sliding mode control backstepping control hydraulic actuator

Numerical modeling for rockbursts:A state-of-the-art review

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 457-478页

作者： Jun Wang Derek B.Apel Yuanyuan Pu Robert Hall Chong Wei Mohammadali Sepehri School of Mining and Petroleum Engineering University of AlbertaEdmontonAlbertaT6G 2R3Canada State Key Laboratory of Coal Mine Disaster dynamics and Control Chongqing UniversityChongqing400044China

As the depth of excavation increases,rockburst becomes one of the most serious geological hazards damaging equipment and facilities and even causing fatalities in mining and civil *** has forced researchers worldwide to identify different methods to investigate rockburst-related ***,some problems,such as the mechanisms and the prediction of rockbursts,continue to be studied because rockburst is a very complicated phenomenon influenced by the uncertainty and complexity in geological conditions,in situ stresses,induced stresses,*** modeling is a widely used method for investigating *** date,great achievements have been made owing to the rapid development of information technology(IT)and computer ***,it is necessary and meaningful to conduct a review of the current state of the studies for rockburst numerical *** this paper,the categories and the origin of different numerical approaches employed in modeling rockbursts are reviewed and the current usage of various numerical modeling approaches is investigated by a literature ***,a state-of-the-art review is implemented to investigate the application of numerical modeling in the mechanism study,and prediction and prevention of *** main achievements and problems are ***,this paper discusses the limitations and the future research of numerical modeling for *** approach is proposed to provide researchers with a systematic and reasonable numerical modeling framework.

关键词： Rockburst Numerical modeling Rockburst mechanism dynamic modeling

Underconstrained Cable-Driven Parallel Suspension System of Virtual Flight Test Model in Wind Tunnel

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Computer modeling in Engineering & Sciences 2023年第4期135卷 395-416页

作者： Huisong Wu Kaichun Zeng Li Yu Yan Li Xiping Kou Institute of High Speed Aerodynamics China Aerodynamics Research and Development CenterMianyang621000China

An underconstrained cable-driven parallel robot(CDPR)suspension system was designed for a virtual flight testing(VFT)*** mechanism includes two identical upper and lower kinematic chains,each of which comprises a cylindrical pair,rotating pair,and cable *** model is pulled via two cables at the top and bottom and fixed by a yaw turntable,which can realize free coupling and decoupling with three rotational degrees of freedom of the ***,the underconstrained CDPR suspension system of the VFT model was designed according to the mechanics theory,the degrees of freedom were verified,and the support platform was optimized to realize the coincidence between the model’s center of mass and the rotation center of the mechanism during the motion to ensure the stability of the support ***,kinematic and dynamical modeling of the underconstrained CDPR suspension system was conducted;the system stiffness and stability criteria were ***,the modeling of an underconstrained,reconfigurable,passively driven CDPR was understood ***,dynamic simulations and experiments were used to verify that the proposed system meets the support requirements of the wind tunnel-based VFT *** study serves as the foundation for subsequent wind tunnel test research on identifying the aerodynamic parameters of aircraft models,and also provides new avenues for the development of novel support methods for thewind tunnel testmodel.

关键词： Virtual flight underconstrained cable-driven dynamic modeling stiffness and stability simulation analysis and experiment

dynamical modeling and controllability analysis of a flexible needle in soft tissue

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International Journal of modeling, Simulation, and Scientific Computing 2014年第2期5卷 130-157页

作者： Arefeh Boroomand Mahdi Tavakoli Ron Sloboda Nawaid Usmani Department of Electrical and Computer Engineering University of Alberta EdmontonABCanada T6G 2V4 Department of Medical Physics Cross Cancer Institute 11560 University AvenueEdmontonABCanada T6G 1Z2 Department of Radiation Oncology Cross Cancer Institute 11560 University AvenueEdmontonABCanada T6G 1Z2

This paper is concerned with deriving a dynamic model of a moderately flexible needle inserted into soft tissue,where the model’s output is the needle *** main advantages of the proposed dynamic modeling approach are that the presented model structure involves parameters that are all measurable or identifiable by simple exper-iments and that it considers the same inputs that are currently used in the clinical practice of manual needle *** manual needle insertion suffers from the fact that flexible needles bend during insertion and their trajectories often vary from those planned,resulting in positioning *** of needle insertion accuracy via robot-assisted needle steering has received significant attention in the past decade.A common assumption in previous research has been that the needle behavior during insertion can be adequately described by static models relating the needle’s forces and torques to its *** closed-loop control purposes,however,a dynamic model of the flexible needle in soft tissue is *** this paper,we propose a Lagrangian-based dynamic model for the coupled needle/tissue system,and analyze the response of the dynamic ***(controllability)analysis is also performed,which is only possible with a dynamic *** proposed dynamic model can serve as a cornerstone of future research into designing dynamics-based control strategies for closed-loop needle steering in soft tissue aimed at minimizing position error.

关键词： dynamic modeling controllability flexible needle

dynamics and Control of Grinding Machine with Micropositioning Workpiece Table

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Transactions of Tianjin University 2006年第3期12卷 157-162页

作者：田延岭张大卫) 闫兵 School of Mechanical Engineering Tianjin University Tianjin 300072China School of Mechanical Engineering Tianjin University of Technology and Education Tianjin 300222 China

To improve the machining precision of a surface grinding machine, a micropositioning workpiece table with high performance was used as auxiliary infeed mechanism to implement nanometer level positioning and dynamic compensation. To better understand the characteristics of the grinding machine modulated with micropositioning workpiece table, the dynamic model of the grinding system was established with modal synthesis and Lagrange＇s equation methods. The grinding system was divided into five subsystems. For each subsystem, the generalized kinematic and potential energies were obtained. Accordingly the dynamic model of the grinding system was given in the modal domain. The waviness of the grinding process was achieved based on the wheel and workpiece vibration. A nonlinear proportional integral derivative （PID） controller with differential trackers was developed to realize dynamic control. The simulation results show that the machining accuracy of the workpiece can be effectively improved by utilizing the micropositioning workpiece table to implement dynamic compensation. An experimental test was carried out to verify the proposed method, and the waviness of the workpiece can be reduced from 0.46 μm to 0.10 μm.

关键词： micropositioning workpiece table surface grinding dynamic modeling nonlinear PID controller

Review of construction methods for whole-cell computational models

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Systems Microbiology and Biomanufacturing 2022年第2期2卷 259-270页

作者： Jingru Zhou Xingcun Fan Lingfeng Cao Huijie Sun Jianye Xia XueFeng Yan State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai 200237China Tianjin Institute of Industrial Biotechnology Chinese Academy of ScienceTianjin 300308China Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237People’s Republic of China

The complex mechanisms of the internal operation of cellular functions have not been fully resolved and these functions are regulated by multiple effects,such as transcription regulation,signal transduction,and enzyme catalysis,forming complex interactive *** makes the construction of a whole-cell computational model,containing various complex cellular functions,very ***,biological models have played a significant role in the field of systems biology,such as guiding gene-target mining and studying cell metabolic ***,there is increasing research interest in the construction of whole-cell computational *** two classical languages of systems biology,this review expounds on the development and challenges of whole-cell computational modeling from the two classical methods of steady-state and dynamic ***,we propose a new approach for constructing whole-cell computational models.

关键词： Whole-cell computational model Systems biology Steady-state dynamic modeling

First order dynamics approaching of broiler chicken deep body temperature response to step changes in ambient temperature

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International Journal of Agricultural and Biological Engineering 2017年第4期10卷 13-21页

作者： Takoi K.Hamrita Richard H.Conway College of Engineering University of GeorgiaDriftmier Engineering CenterAthensGeorgia 30602USA United Technologies Corporation 700 Olympic Dr.Athens GA 30601USA

Traditional environmental control methods for poultry housing which rely solely on environmental factors fall short in meeting thermal and physiological needs of the *** methods are needed that factor in the physiological needs and responses of the animals in order to maximize well-being of the animals and minimize heat *** body temperature(DBT)has been shown in the literature to be a strong indicator of heat stress,therefore studies are needed that help us gain a deeper understanding of the relationship between this variable and environmental *** aim of this study was to identify the order of the dynamic response of poultry DBT to large step changes in ambient temperature(AT).Temperature steps had to be big enough to take the chickens out of their homeothermic zone.A total of 46 DBT/AT data sets with 23 upward AT steps and 23 downward AT steps were obtained using a biotelemetry system,and involving three *** responses of individual chickens to step changes in AT were found to have a 0.88 average Pearson correlation suggesting consistency in chickens’responses to the same stimuli(pdynamic response of poultry DBT to large step changes in ambient temperature follows a first order *** further studies are needed to more fully derive the model,this study provided a stepping-stone towards gaining a better understanding of the relationship between DBT and AT,therefore taking us one step closer towards making optimal management and risk assessment decisions that are based on physiological needs of the c

关键词： environmental control ambient temperature deep body temperature biotelemetry step response dynamic modeling broiler chicken physiological responses

Data-driven prediction of temperature variations in an open cathode proton exchange membrane fuel cell stack using Koopman operator

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Energy and AI 2023年第4期14卷 439-450页

作者： Da Huo Carrie M.Hall Mechanical Materialsand Aerospace Engineering DepartmentIllinois Institute of Technology10 West 35th StreetChicago60616ILUnited States

In this study,a novel application of the Koopman operator for control-oriented modeling of proton exchange membrane fuel cell(PEMFC)stacks is *** primary contributions of this paper are:(1)the design of Koopman-based models for a fuel cell stack,incorporating K-fold cross-validation,varying lifted dimensions,radial basis functions(RBFs),and prediction horizons;and(2)comparison of the performance of Koopman-based approach with a more traditional physics-based *** results demonstrate the high accuracy of the Koopman-based model in predicting fuel cell stack behavior,with an error of less than 3%.The proposed approach offers several advantages,including enhanced computational efficiency,reduced computational burden,and improved *** study demonstrates the suitability of the Koopman operator for the modeling and control of PEMFCs and provides valuable insights into a novel control-oriented modeling approach that enables accurate and efficient predictions for fuel cell stacks.

关键词： Proton exchange membrane fuel cell(PEMFC) Data-driven modeling Koopman operator dynamic modeling Control-oriented modeling Physics-based modeling