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Cumulative thermal coupling modeling and analysisof oil-immersed motor-pump assembly forelectro–hydrostatic actuator 被引量:1
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作者 Siming FAN Shaoping WANG +3 位作者 Qiyang WANG Xingjian WANG Di LIU Xiao WU 《Chinese Journal of Aeronautics》 2025年第5期394-410,共17页
The Electro–Hydrostatic Actuator(EHA)is applied to drive the control surface in flightcontrol system of more electric aircraft.In EHA,the Oil-Immersed Motor Pump(OMP)serves asthe core as a power assembly.However,the ... The Electro–Hydrostatic Actuator(EHA)is applied to drive the control surface in flightcontrol system of more electric aircraft.In EHA,the Oil-Immersed Motor Pump(OMP)serves asthe core as a power assembly.However,the compact integration of the OMP presents challenges inefficiently dissipating internal heat,leading to a performance degradation of the EHA due to ele-vated temperatures.Therefore,accurately modeling and predicting the internal thermal dynamicsof the OMP hold considerable significance for monitoring the operational condition of the EHA.In view of this,a modeling method considering cumulative thermal coupling was hereby proposed.Based on the proposed method,the thermal models of the motor and the pump were established,taking into account heat accumulation and transfer.Taking the leakage oil as the heat couplingpoint between the motor and the pump,the dynamic thermal coupling model of the OMP wasdeveloped,with the thermal characteristics of the oil considered.Additionally,the comparativeexperiments were conducted to illustrate the efficiency of the proposed model.The experimentalresults demonstrate that the proposed dynamic thermal coupling model accurately captured thethermal behavior of OMP,outperforming the static thermal parameter model.Overall,thisadvancement is crucial for effectively monitoring the health of EHA and ensuring flight safety. 展开更多
关键词 Electro-hydrostatic actuator Oil-immersed motor-pump Dynamic thermal coupling model Heat transfer Heat accumulation
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Progress on Multi-Field Coupling Simulation Methods in Deep Strata Rock Breaking Analysis
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作者 Baoping Zou Chenhao Pei +3 位作者 Qizhi Chen Yansheng Deng Yongguo Chen Xu Long 《Computer Modeling in Engineering & Sciences》 2025年第3期2457-2485,共29页
The utilization of multi-field coupling simulation methods has become a pivotal approach for the investigation of intricate fracture behavior and interaction mechanisms of rock masses in deep strata.The high temperatu... The utilization of multi-field coupling simulation methods has become a pivotal approach for the investigation of intricate fracture behavior and interaction mechanisms of rock masses in deep strata.The high temperatures,pressures and complex geological environments of deep strata frequently result in the coupling of multiple physical fields,including mechanical,thermal and hydraulic fields,during the fracturing of rocks.This review initially presents an overview of the coupling mechanisms of these physical fields,thereby elucidating the interaction processes ofmechanical,thermal,and hydraulic fields within rockmasses.Secondly,an in-depth analysis ofmulti-field coupling is conducted from both spatial and temporal perspectives,with the introduction of simulation methods for a range of scales.It emphasizes cross-scale coupling methodologies for the transfer of rock properties and physical field data,including homogenization techniques,nested coupling strategies and data-driven approaches.To address the discontinuous characteristics of the rock fracture process,the review provides a detailed explanation of continuousdiscontinuous couplingmethods,to elucidate the evolution of rock fracturing and deformationmore comprehensively.In conclusion,the review presents a summary of the principal points,challenges and future directions of multi-field coupling simulation research.It also puts forward the potential of integrating intelligent algorithms with multi-scale simulation techniques to enhance the accuracy and efficiency of multi-field coupling simulations.This offers novel insights into multi-field coupling simulation analysis in deep rock masses. 展开更多
关键词 multi-field coupling numerical simulation MULTI-SCALE information transfer DISCONTINUITY
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Analysis of multi-field coupling behaviors of sandwich piezoelectric semiconductor beams under thermal loadings
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作者 Dejuan KONG Zhuangzhuang HE +1 位作者 Chengbin LIU Chunli ZHANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第8期1571-1590,共20页
Sandwich piezoelectric semiconductor(PS)structures have significant applications in multi-functional semiconductor devices.The analysis of multi-field coupling behaviors of PS structures is of fundamental importance i... Sandwich piezoelectric semiconductor(PS)structures have significant applications in multi-functional semiconductor devices.The analysis of multi-field coupling behaviors of PS structures is of fundamental importance in developing novel PS devices.In this paper,we develop a general temperature-deformation-polarization-carrier(TDPC)coupling model for sandwich-type PS beams involving pyroelectricity under thermal loadings,based on three-dimensional(3D)basic equations of the thermo-piezoelectric semiconductor(TPS).We derive analytical solutions for extensional,bending,and buckling deformations of simply-supported sandwich n-type PS beams subjected to open-circuit and electrically isolated boundary conditions.The accuracy of the proposed model in this paper is verified through finite element simulations implemented in the COMSOL software.Numerical results show that the initial electron concentration and the thickness ratio of the PS layer to the beam's total thickness have a significant effect on thermally induced extensional and bending responses,as well as critical buckling mechanical and thermal loadings.This study provides a theoretical framework and guidance for designing semiconductor devices based on sandwich PS beam structures. 展开更多
关键词 piezoelectric semiconductor(PS) sandwich beam multi-field coupling behavior critical buckling thermal loading analytical solution
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Failure microscopic mechanism and damage constitutive model of dolomite under water-rock coupling interaction
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作者 SUN Xiao-ming ZHANG Jing +6 位作者 SHI Fu-kun HE Lin-sen ZHANG Yong MIAO Cheng-yu DING Jia-xu MA Li-sha ZHAO Hao-ze 《Journal of Central South University》 2025年第4期1431-1446,共16页
To investigate the effects of water and cyclic loading on dolomite’s mechanical properties during deep mining,mechanical experiments on non-pressure water absorption and cyclic loading were conducted.The findings rev... To investigate the effects of water and cyclic loading on dolomite’s mechanical properties during deep mining,mechanical experiments on non-pressure water absorption and cyclic loading were conducted.The findings reveal that the elastic modulus and Poisson ratio of dolomite fluctuate with increasing water content.The mass of water absorption is positively correlated with time and the water absorption stage can be divided into three stages:accelerated,decelerated,and stabilized stages.During this process,the number of pores in dolomite increases,while the pore diameter initially decreases and then fluctuates.Microscopic analysis shows that the proportion of mesopores first increases and then decreases,while micropores exhibit the opposite trend,and the proportion of macropores fluctuates around 0%.A model diagram of structural evolution during water absorption has been developed.Additionally,the softening process of dolomite’s water absorption strength is categorized into three stages:a relatively stable stage,an accelerated softening stage dominated by mesopore water absorption,and a decelerated softening stage characterized by micropore water absorption.A uniaxial damage constitutive model for dolomite under water influence was established based on the Weibull distribution and Mohr-Coulomb strength criterion,and experimental validation indicates its strong applicability. 展开更多
关键词 water-rock coupling DOLOMITE constitutive model MICROSTRUCTURE loading-unloading cycle
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Computational Modeling of the Prefrontal-Cingulate Cortex to Investigate the Role of Coupling Relationships for Balancing Emotion and Cognition
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作者 Jinzhao Wei Licong Li +3 位作者 Jiayi Zhang Erdong Shi Jianli Yang Xiuling Liu 《Neuroscience Bulletin》 2025年第1期33-45,共13页
Within the prefrontal-cingulate cortex,abnormalities in coupling between neuronal networks can disturb the emotion-cognition interactions,contributing to the development of mental disorders such as depression.Despite ... Within the prefrontal-cingulate cortex,abnormalities in coupling between neuronal networks can disturb the emotion-cognition interactions,contributing to the development of mental disorders such as depression.Despite this understanding,the neural circuit mechanisms underlying this phenomenon remain elusive.In this study,we present a biophysical computational model encompassing three crucial regions,including the dorsolateral prefrontal cortex,subgenual anterior cingulate cortex,and ventromedial prefrontal cortex.The objective is to investigate the role of coupling relationships within the prefrontal-cingulate cortex networks in balancing emotions and cognitive processes.The numerical results confirm that coupled weights play a crucial role in the balance of emotional cognitive networks.Furthermore,our model predicts the pathogenic mechanism of depression resulting from abnormalities in the subgenual cortex,and network functionality was restored through intervention in the dorsolateral prefrontal cortex.This study utilizes computational modeling techniques to provide an insight explanation for the diagnosis and treatment of depression. 展开更多
关键词 Prefrontal-cingulate cortex Computational modeling coupling relationships DEPRESSION Emotion and cognition
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New insights on generalized heat conduction and thermoelastic coupling models
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作者 Yue HUANG Lei YAN +1 位作者 Hua WU Yajun YU 《Applied Mathematics and Mechanics(English Edition)》 2025年第8期1533-1550,共18页
With the miniaturization of devices and the development of modern heating technologies,the generalization of heat conduction and thermoelastic coupling has become crucial,effectively emulating the thermodynamic behavi... With the miniaturization of devices and the development of modern heating technologies,the generalization of heat conduction and thermoelastic coupling has become crucial,effectively emulating the thermodynamic behavior of materials in ultrashort time scales.Theoretically,generalized heat conductive models are considered in this work.By analogy with mechanical viscoelastic models,this paper further enriches the heat conduction models and gives their one-dimensional physical expression.Numerically,the transient thermoelastic response of the slim strip material under thermal shock is investigated by applying the proposed models.First,the analytical solution in the Laplace domain is obtained by the Laplace transform.Then,the numerical results of the transient responses are obtained by the numerical inverse Laplace transform.Finally,the transient responses of different models are analyzed and compared,and the effects of material parameters are discussed.This work not only opens up new research perspectives on generalized heat conductive and thermoelastic coupling theories,but also is expected to be beneficial for the deeper understanding of the heat wave theory. 展开更多
关键词 generalized heat conduction thermoelastic coupling transient response generalized Cattaneo-Vernotte(CV)model generalized Green-Naghdi(GN)model
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Optimal Coupling Height of the Atmosphere and Land Surface——An Earth System Modeling Perspective
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作者 Shaofeng LIU Xubin ZENG +6 位作者 Yongjiu DAI Hua YUAN Nan WEI Zhongwang WEI Xingjie LU Shupeng ZHANG Michael A.BRUNKE 《Advances in Atmospheric Sciences》 2025年第3期417-426,共10页
In Earth system modeling,the land surface is coupled with the atmosphere through surface turbulent fluxes.These fluxes are computed using mean meteorological variables between the surface and a reference height in the... In Earth system modeling,the land surface is coupled with the atmosphere through surface turbulent fluxes.These fluxes are computed using mean meteorological variables between the surface and a reference height in the atmosphere.However,the dependence of flux computation on the reference height,which is usually set as the lowest level in the atmosphere in Earth system models,has not received much attention.Based on high-resolution large-eddy simulation(LES)data under unstable conditions,we find the setting of reference height is not trivial within the framework of current surface layer theory.With a reasonable prescription of aerodynamic roughness length(following the setting in LESs),reference heights near the top of the surface layer tend to provide the best estimate of surface fluxes,especially for the momentum flux.Furthermore,this conclusion for the sensible heat flux is insensitive to the ratio of roughness length for momentum versus heat.These results are robust,whether using the classical or revised surface layer theory.They provide a potential guide for setting the proper reference heights for Earth system modeling and can be further tested in the near future using observational data from land–atmosphere feedback observatories. 展开更多
关键词 surface flux estimate reference height land surface modeling atmosphere-land surface coupling large-eddy simulation
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Simulation of the future evolution track of“production-living-ecological”space in a coastal city based on multimodel coupling and wetland protection scenarios
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作者 Yitong Yin Rongjin Yang +5 位作者 Zechen Song Yuying Zhang Yanrong Lu Le Zhang Meiying Sun Xiuhong Li 《Geography and Sustainability》 2025年第3期51-63,共13页
Coastal cities hold a special position in the fields of production,living,and ecological research because of their unique wetland resource advantages.However,with global urbanization and rapid economic development,con... Coastal cities hold a special position in the fields of production,living,and ecological research because of their unique wetland resource advantages.However,with global urbanization and rapid economic development,con-flicts among production,living and ecological land are prevalent in coastal cities in the process of maintaining sustainable wetland resources and further developing the social economy.By establishing an SD-PLUS-CCD cou-pling model,this paper analysed the evolution characteristics and driving mechanism of the production-living-ecological space(PLES)and the effects of wetland protection(WLP)on promoting or inhibiting the coordinated development of the PLES in Dongying city during 2005-2060.The results show that(1)from 2005 to 2020,the increase in urban population resulted in a significant transfer of arable land and a reduction of 914 km2 in pro-duction space(PS);(2)from 2020 to 2060,under the WLP scenario,the conversion of wetland ecological space will reduce the PS and living space(LS)by 193.92 km2 and 107.14 km2,respectively,and increase the ecological space(ES)by 327.52 km2;and(3)wetland protection has an inhibitory effect on the coordinated development of PLES in the study area,and the total proportion of noncoordinated areas of PE and living-ecological space will continue to increase during the simulation period.This paper provides a solid theoretical support for the sustain-able management and protection of wetlands in coastal cities and possible PLES conflict patterns and provides a scientific basis for future territorial spatial planning and policy balance analysis. 展开更多
关键词 Wetland protection “Production-living-ecological”space coupling model Driving mechanism Coordinated and sustainable development
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Numerical simulation of the fluid and flexible rods interaction using a semi-resolved coupling model promoted by anisotropic Gaussian kernel function
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作者 Caiping Jin Jingxin Zhang Yonglin Sun 《Theoretical & Applied Mechanics Letters》 2025年第1期5-8,共4页
The numerical simulation of the fluid flow and the flexible rod(s)interaction is more complicated and has lower efficiency due to the high computational cost.In this paper,a semi-resolved model coupling the computatio... The numerical simulation of the fluid flow and the flexible rod(s)interaction is more complicated and has lower efficiency due to the high computational cost.In this paper,a semi-resolved model coupling the computational fluid dynamics and the flexible rod dynamics is proposed using a two-way domain expansion method.The gov-erning equations of the flexible rod dynamics are discretized and solved by the finite element method,and the fluid flow is simulated by the finite volume method.The interaction between fluids and solid rods is modeled by introducing body force terms into the momentum equations.Referred to the traditional semi-resolved numerical model,an anisotropic Gaussian kernel function method is proposed to specify the interactive forces between flu-ids and solid bodies for non-circle rod cross-sections.A benchmark of the flow passing around a single flexible plate with a rectangular cross-section is used to validate the algorithm.Focused on the engineering applications,a test case of a finite patch of cylinders is implemented to validate the accuracy and efficiency of the coupled model. 展开更多
关键词 Semi-resolved coupling model Two-way domain expansion method Anisotropic Gaussian kernel function Flexible rod(s)
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COUPLING MODEL OF EXTENDED MANUFACTURING ORGANIZATION AND ITS APPLICATION 被引量:1
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作者 郭宇 安波 廖文和 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第1期137-144,共8页
For the feature of complex weapon manufacturing on internet,a coupling model is proposed.By using the model,the correlation between manufacturing cells in an extended manufacturing organization can be evaluated quanti... For the feature of complex weapon manufacturing on internet,a coupling model is proposed.By using the model,the correlation between manufacturing cells in an extended manufacturing organization can be evaluated quantitatively,so an appropriate control plan is determined.A strategy to improve and reduce the coupling relationship of the organization is studied.A correlation matrix of extended tasks is built to analyze the relationship between sub-tasks and manufacturing resources.An optimization method for manufacturing resource configuration is presented based on the coupling model.Finally,a software system for analyzing coupling model about manufacturing organization on internet is developed,and the result shows that the coupling model is effective. 展开更多
关键词 networked manufacturing manufacturing organization correlation matrix coupling model
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A Model Coupling Method for Shape Prediction 被引量:15
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作者 WANG Dong-cheng LIU Hong-min 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2012年第2期22-27,共6页
The shape of strip is calculated by iterative method which combines strip plastic deformation model with rolls elastic deformation model through their calculation results, which can be called results coupling method. ... The shape of strip is calculated by iterative method which combines strip plastic deformation model with rolls elastic deformation model through their calculation results, which can be called results coupling method. Be- cause the shape and rolling force distribution are very sensitive to strip thickness transverse distribution% variation, the iterative course is rather unstable and sometimes convergence cannot be achieved. In addition, the calculating speed of results coupling method is low, which restricts its usable range. To solve the problem, a new model cou- pling method is developed, which takes the force distribution between rolls, rolling force distribution and strip's exit transverse displacement distribution as basic unknowns, and integrates strip plastic deformation model and rolls elas- tic deformation model as a unified linear equations through their internal relation, so the iterative calculation between the strip plastic deformation model and rolls elastic deformation model can be avoided. To prove the effectiveness of the model coupling method, two examples are calculated by results coupling method and model coupling method re- spectively. The results of front tension stress, back tension stress, strip^s exit gauge, the force between rolls and rolling force distribution calculated by model coupling method coincide very well with results coupling method. How- ever the calculation course of model coupling method is more steady than results coupling method, and its calculating speed is about ten times as much as the maximal speed of results coupling method, which validates its practicability and reliability. 展开更多
关键词 shape prediction results coupling method model coupling method strip plastic deformation rolls elas-tic deformation
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Coupling Dynamic Model of Chatter for Cold Rolling 被引量:10
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作者 YANG Xu TONG Chao-nan +1 位作者 YUE Guang-feng MENG Jian-ji 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2010年第12期30-34,共5页
In order to build high accuracy integral dynamic models of cold rolling mill system, by analyzing the vibration process of cold rolling, the dynamic model of 4-h mill, including the rolling process model, the mill rol... In order to build high accuracy integral dynamic models of cold rolling mill system, by analyzing the vibration process of cold rolling, the dynamic model of 4-h mill, including the rolling process model, the mill roll stand structure model and the hydraulic servo system model is built. These three models are coupled and linearized, then the multiple input and multiple output (MIMO) linear transfer function model of single stand 4-h cold mill system is obtained. The model with the proposed data proves its validity, meanwhile the effects of different working conditions on the stability of cold rolling mill system have been discussed. Simulation resulsts show that the model accords with former models and has its own advancement. It contributes to the further study and supression of coupling vibraiton. 展开更多
关键词 cold rolling chatter dynamic modeling coupling SIMULATION
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The dynamic coupling model and its application of urbanization and eco-environment in Hexi Corridor 被引量:9
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作者 QIAO Biao FANG Chuanglin 《Journal of Geographical Sciences》 SCIE CSCD 2005年第4期491-499,共9页
This paper, taking Hexi Corridor as an example, analyzes the altemating intimidation and the dynamic evolving relation between urbanization and eco-environment in arid area of West China. We argue that the harmonious ... This paper, taking Hexi Corridor as an example, analyzes the altemating intimidation and the dynamic evolving relation between urbanization and eco-environment in arid area of West China. We argue that the harmonious development system of the urbanization and eco-environment would go through four phases: rudimentary symbiotic phase, harmonious developmental phase, utmost increasing phase and spiral type rising phase. Throughout the four phases, the elements of the system would influence each other, coerce each other, and complete the spiral type rising process from low-grade symbiosis to high-grade harmony together. The study on Hexi Corridor shows that the urbanization level in Hexi Corridor has increased gradually from 1985 to 2003 accompanied with the fluctuations of eco-environment state. The response of eco-environment to urbanization has been evident, but lagged behind the urbanization course. At present, the harmonious development system in Hexi Corridor was in its harmonious developmental phase. However, the coupling degree has increased quickly and approached 90 yet, which is signaling that the system is about to enter the utmost increasing phase, and the ecological crisis will enter the latent period. We have found that the coupling degree can well reflect the interactive coercing and dynamic evolving situation between urbanization and eco-environment in Hexi Corridor. From the temporal change of the coupling degree, it can be concluded that urbanization sometimes needs to pay a certain cost for the damage of the eco-environment in its initial stages, but as the urbanization continues, the state of the eco-environment would be meliorated. 展开更多
关键词 Hexi Corridor URBANIZATION eeo-environment harmonious development dynamic coupling model
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A Numerical Study on Effects of Land-Surface Heterogeneity from' Combined Approach' on Atmospheric ProcessPart II: Coupling-Model Simulations 被引量:5
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作者 曾新民 赵鸣 苏炳凯 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2000年第2期241-255,共15页
Two land surface schemes, one the standard Biosphere / Atmosphere Transfer Scheme Version ie (BOZ) and the other B1Z based on B0Z and heterogeneously-treated by' combined approach' , were co 'pled to the m... Two land surface schemes, one the standard Biosphere / Atmosphere Transfer Scheme Version ie (BOZ) and the other B1Z based on B0Z and heterogeneously-treated by' combined approach' , were co 'pled to the meso-scale model MM4, respectively. Through the calculations of equations from the companion paper, parameters representing land surface heterogeneity and suitable for the coupling models were found out. Three cases were simulated for heavy rainfalls during 36 hours, and the sensitivity of short-term weather modeling to the land surface heterogeneity was tested. Through the analysis of the simulations of the three heavy rainfalls, it was demonstrated that BIZ, compared with BOZ, could more realistically reflect the features of the land surface heterogeneity, therefore could more realistically reproduce the circulation and precipitation amount in the heavy rainfall processes of the three cases. This shows that even short-term weather is sensitive to the land surface heterogeneity, which is more obvious with time passing, and whose influence is more pronounced in the lower layer and gradually extends to the middle and upper layer. Through the analysis of these simulations with BlZ, it is suggested that the bulk effect of smaller-scale fluxes (i.e., the momentum, water vapor and sensible heat fluxes) near the s ig nificantly-heterogeneous land surface is to change the larger-scale (i.e., meso-scale) circulation, and then to influence the development of the low-level jets and precipitation. And also, the complexity of the land-atmosphere interaction was shown in these simulations. 展开更多
关键词 Combined approach Land surface heterogeneity coupling model Numerical experiment
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Analysis of a Water-Inrush Disaster Caused by Coal Seam Subsidence Karst Collapse Column under the Action of Multi-Field Coupling in Taoyuan Coal Mine 被引量:6
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作者 Zhibin Lin Boyang Zhang Jiaqi Guo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第1期311-330,共20页
Minin-induced water inrush from a confined aquifer due to subsided floor karst collapse column(SKCC)is a type of serious disaster in the underground coal extraction.Karst collapse column(KCC)developed in a confined aq... Minin-induced water inrush from a confined aquifer due to subsided floor karst collapse column(SKCC)is a type of serious disaster in the underground coal extraction.Karst collapse column(KCC)developed in a confined aquifer occurs widely throughout northern China.A water inrush disaster from SKCC occurred in Taoyuan coal mine on February 3,2013.In order to analyze the effect of the KCC influence zone’s(KCCIZ)width and the entry driving distance of the water inrush through the fractured channels of the SKCC,the stress,seepage,and impact dynamics coupling equations were used tomodel the seepage rule,and a numerical FLAC3D model was created to determine the plastic zones,the vertical displacement development of the rockmass surrounding the entry driving working face(EDWF),and the seepage vector and water inflow development of the seepage field.The hysteretic mechanism of water inrush due to SKCC in Taoyuan coal mine was investigated.The results indicate that a water inrush disaster will occur when the width of the KCCIZ exceeds 16 m under a driving,which leads to the aquifer connecting with the fractured zones of the entry floor.Hysteretic water inrush disasters are related to the stress release rate of the surrounding rocks under the entry driving.When the entry driving exceeds about 10 m from the water inrush point,the stress release rate reaches about 100%,and a water inrush disaster occurs. 展开更多
关键词 Karst collapse column multi-field coupling seepage mutation water-inrush
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A Model of Debris Flow Forecast Based on the Water-Soil Coupling Mechanism 被引量:6
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作者 Shaojie Zhang Hongjuan Yang +2 位作者 Fangqiang Wei Yuhong Jiang Dunlong Liu 《Journal of Earth Science》 SCIE CAS CSCD 2014年第4期757-763,共7页
Debris flow forecast is an important means of disaster mitigation. However, the accuracy of the statistics-based debris flow forecast is unsatisfied while the mechanism-based forecast is unavailable at the watershed s... Debris flow forecast is an important means of disaster mitigation. However, the accuracy of the statistics-based debris flow forecast is unsatisfied while the mechanism-based forecast is unavailable at the watershed scale because most of existing researches on the initiation mechanism of debris flow took a single slope as the main object. In order to solve this problem, this paper developed a model of debris flow forecast based on the water-soil coupling mechanism at the watershed scale. In this model, the runoff and the instable soil caused by the rainfall in a watershed is estimated by the distrib- uted hydrological model (GBHM) and an instable identification model of the unsaturated soil. Because the debris flow is a special fluid composed of soil and water and has a bigger density, the density esti- mated by the runoff and instable soil mass in a watershed under the action of a rainfall is employed as a key factor to identify the formation probability of debris flow in the forecast model. The Jiangjia Gulley, a typical debris flow valley with a several debris flow events each year, is selected as a case study watershed to test this forecast model of debris flow. According the observation data of Dongchuan Debris Flow Observation and Research Station, CAS located in Jiangjia Gulley, there were 4 debris flow events in 2006. The test results show that the accuracy of the model is satisfied. 展开更多
关键词 debris flow forecast watershed scale soil-water coupling distributed hydrological model limit equilibrium analysis Jiangjia Gulley.
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Numerical analysis of stability for mined-out area in multi-field coupling 被引量:5
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作者 罗周全 谢承煜 +3 位作者 周吉明 贾楠 刘晓明 徐海 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期669-675,共7页
There were differences between real boundary and blast hole controlling boundary of irregular mined-out area in underground metal mines. There were errors in numerical analysis of stability for goaf, if it was analyze... There were differences between real boundary and blast hole controlling boundary of irregular mined-out area in underground metal mines. There were errors in numerical analysis of stability for goaf, if it was analyzed as regular 3D mined-out area and the influence of coupling stress-seepage-disturbance was not considered adequately. Taking a lead zinc mine as the background, the model was built by the coupling of Surpac and Midas-Gts based on the goaf model precisely measured by CMS.According to seepage stress fundamental equations based on the equivalent continuum mechanical and the theory about equivalent load of dynamic disturbance in deep-hole blasting, the stability of mined-out area under multi-field coupling of stress-seepage-dynamic disturbance was numerically analyzed. The results show that it is more consistent between the numerical analysis model based on the real model of irregular 3D shape goaf and the real situation, which could faithfully reappear the change rule of stress–strain about the surrounding rock under synthetic action of blasting dynamic loading and the seepage pressure. The mined-out area multi-field coupling formed by blasting excavation is stable. Based on combination of the advantages of the CMS,Surpac and Midas-Gts, and fully consideration of the effects of multi-field coupling, the accurate and effective way could be provided for numerical analysis of stability for mined-out area. 展开更多
关键词 mined-out area measured actually multi-field coupling stress-seepage-disturbance stability for mined-out area
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Heat-fluid-solid coupling model for gas-bearing coal seam and numerical modeling on gas drainage promotion by heat injection 被引量:6
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作者 Ruifu Yuan Chunling Chen +1 位作者 Xiao Wei Xiaojun Li 《International Journal of Coal Science & Technology》 EI 2019年第4期564-576,共13页
Improving the absorbed gas to active desorption and seepage and delaying gas drainage attenuation are considered as key methods for increasing drainage efficiency and gas output.According to the solid mechanics theory... Improving the absorbed gas to active desorption and seepage and delaying gas drainage attenuation are considered as key methods for increasing drainage efficiency and gas output.According to the solid mechanics theory,the nonlinear Darcy seepage theory and thermodynamics,the heat-fluid-solid coupling model for gassy coal has been improved.The numerical model was founded from the improved multi-field coupling model by COMSOL Multiphysics and gas drainage by borehole down the coal seam enhanced by heat injection was modelled.The results show that the heatfluid-solid model with adsorption effects for gassy coal was well simulated by the improved multi-field model.The mechanism of coal seam gas desorption seepage under the combined action of temperature,stress and adsorption can be well described.Gas desorption and seepage can be enhanced by heat injection into coal seams.The gas drainage rate was directly proportional to the temperature of injected heat in the scope of 30-150 ℃ and increasing in the whole modelleddrainage process (0-1000 d).The increased level was maximum in the initial drainage time and decreasing gradually along with drainage time.The increasing ratio of drainage rate was maximum when the temperature raised from 30 to 60 ℃.Although the drainage rate would increase along with increasing temperature,when exceeding 60 ℃,the increasing ratio of drainage rate with rising temperature would decrease.Gas drainage promotion was more effective in coal seams with lower permeability than with higher permeability.The coal seam temperature in a 5 m distance surrounding the heat injection borehole would rise to around 60 ℃ in 3 months.That was much less than the time of gas drainage in the coal mines in sites with low permeability coal seams.Therefore,it is valuable and feasible to inject heat into coal seams to promote gas drainage,and this has strong feasibility for coal seams with low permeability which are widespread in China. 展开更多
关键词 Gassy COAL Heat-fluid-solid coupling model Heat injection GAS extraction Numerical modeling
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A generalized multi-field coupling approach and its application to stability and deformation control of a high slope 被引量:5
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作者 Chuangbing Zhou Yifeng Chen +1 位作者 Qinghui Jiang Wenbo Lu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2011年第3期193-206,共14页
Human activities, such as blasting excavation, bolting, grouting and impounding of reservoirs, will lead to disturbances to rock masses and variations in their structural features and material properties. These engine... Human activities, such as blasting excavation, bolting, grouting and impounding of reservoirs, will lead to disturbances to rock masses and variations in their structural features and material properties. These engineering disturbances are important factors that would alter the natural evolutionary processes or change the multi-field interactions in the rock masses from their initial equilibrium states. The concept of generalized multi-field couplings was proposed by placing particular emphasis on the role of engineering disturbances in traditional multi-field couplings in rock masses. A mathematical model was then developed, in which the effects of engineering disturbances on the coupling-processes were described with changes in boundary conditions and evolutions in thermo-hydro-mechanical (THM) properties of the rocks. A parameter, d, which is similar to damage variables but has a broader physical meaning, was conceptually introduced to represent the degree of engineering disturbances and the couplings among the material properties. The effects of blasting excavation, bolting and grouting in rock engineering were illustrated with various field observations or theoretical results, on which the degree of disturbances and the variations in elastic moduli and permeabilities were particularly focused. The influences of excavation and groundwater drainage on the seepage flow and stability of the slopes were demonstrated with numerical simulations. The proposed approach was further employed to investigate the coupled hydro-mechanical responses of a high rock slope to excavation, bolting and impounding of the reservoir in the dam left abutment of Jinping I hydropower station. The impacts of engineering disturbances on the deformation and stability of the slope during construction and operation were demonstrated. 展开更多
关键词 generalized multi-field couplings engineering disturbance slope stability deformation control
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FLUID-SOLID COUPLING MATHEMATICAL MODEL OF CONTAMINANT TRANSPORT IN UNSATURATED ZONE AND ITS ASYMPTOTICAL SOLUTION 被引量:4
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作者 薛强 梁冰 +1 位作者 刘晓丽 李宏艳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第12期1475-1485,共11页
The process of contaminant transport is a problem of multicomponent and multiphase flow in unsaturated zone. Under the presupposition that gas existence affects water transport, a coupled mathematical model of contami... The process of contaminant transport is a problem of multicomponent and multiphase flow in unsaturated zone. Under the presupposition that gas existence affects water transport, a coupled mathematical model of contaminant transport in unsaturated zone has been established based on fluid_solid interaction mechanics theory. The asymptotical solutions to the nonlinear coupling mathematical model were accomplished by the perturbation and integral transformation method. The distribution law of pore pressure, pore water velocity and contaminant concentration in unsaturated zone has been presented under the conditions of with coupling and without coupling gas phase. An example problem was used to provide a quantitative verification and validation of the model. The asymptotical solution was compared with Faust model solution. The comparison results show reasonable agreement between asymptotical solution and Faust solution, and the gas effect and media deformation has a large impact on the contaminant transport. The theoretical basis is provided for forecasting contaminant transport and the determination of the relationship among pressure_saturation_permeability in laboratory. 展开更多
关键词 contaminant transport unsaturated zone numerical model fluid-solid coupling interaction asymptotical solution
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