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Acta Mechanica Sinica 1997年第3期13卷 264-272页

作者：冉启全顾小芸李士伦 Institute of Mechanics Chinese Academy of SciencesBeijing 100080China Southwest Petroleum Institute Nanchong 637001China

A mathematical model for coupled multiphase fluid flow and sedi- mentation deformation is developed based on fluid-solid interaction mechanism.A finite difference-finite element numerical approach is *** results of an example show that the fluid-solid coupled effect has great influence on multiphase fluid flow and reservoir recovery performances,and the coupled model has practical significance for oilfield development.

关键词： reservoir multiphase flow solid deformation coupled model numerical simulation

A coupled model of TiN inclusion growth in GCr15SiMn during solidification in the electroslag remelting process

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1266-1272页

作者： Liang Yang Guo-guang Cheng Shi-jian Li Min Zhao Gui-ping Feng Tao Li State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Dongbei Special Steel Group

TiN inclusions observed in an ingot produced by electroslag remelting （ESR） are extremely harmful to GCrl5SiMn steel. Therefore, accurate predictions of the growth size of these inclusions during steel solidification are significant for clean ESR ingot production. On the basis of our previous work, a coupled model of solute microsegregation and TiN inclusion growth during solidification has been established. The results demonstrate that compared to a non-coupled model, the coupled model predictions of the size of TiN inclusions are in good agreement with experimental results using scanning electron microscopy with energy disperse spectroscopy （SEM-EDS）. Because of high cooling rate, the sizes of TiN inclusions in the edge area of the ingots are relatively small compared to the sizes in the center area. During the ESR process, controlling the content of Ti in the steel is a feasible and effective method of decreasing the sizes of TiN inclusions.

关键词： coupled model solidification inclusions bearing steel electroslag remelting

Biases of the Arctic climate in a regional ocean-sea iceatmosphere coupled model: an annual validation

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Acta Oceanologica Sinica 2014年第9期33卷 56-67页

作者： LIU Xiying College of Meteorology and Oceanography People's Liberation Army University of Science and Technology

The Coupling of three model components, WRF/PCE （polar climate extension version of weather research and forecasting model （WRF））, ROMS （regional ocean modeling system）, and CICE （community ice code）, has been implemented, and the regional atmosphere-ocean-sea ice coupled model named WRF/PCE- ROMS-CICE has been validated against ERA-interim reanalysis data sets for 1989. To better understand the reasons that generate model biases, the WRF/PCE-ROMS-CICE results were compared with those of its components, the WRF/PCE and the ROMS-CICE. There are cold biases in surface air temperature （SAT） over the Arctic Ocean, which contribute to the sea ice concentration （SIC） and sea surface temperature （SST） biases in the results of the WRF/PCE-ROMS-CICE. The cold SAT biases also appear in results of the atmo- spheric component with a mild temperature in winter and similar temperature in summer. Compared to results from the WRF/PCE, due to influences of different distributions of the SIC and the SST and inclusion of interactions of air-sea-sea ice in the WRF/PCE-ROMS-CICE, the simulated SAT has new features. These influences also lead to apparent differences at higher levels of the atmosphere, which can be thought as responses to biases in the SST and sea ice extent. There are similar atmospheric responses in feature of distribution to sea ice biases at 700 and 500 hPa, and the strength of responses weakens when the pressure decreases in January. The atmospheric responses in July reach up to 200 hPa. There are surplus sea ice ex- tents in the Greenland Sea, the Barents Sea, the Davis Strait and the Chukchi Sea in winter and in the Beau- fort Sea, the Chukchi Sea, the East Siberian Sea and the Laptev Sea in summer in the ROMS-CICE. These differences in the SIC distribution can all be explained by those in the SST distributions. These features in the simulated SST and SIC from ROMS-CICE also appear in the WRF/PCE-ROMS-CICE. It is shown that the performance of the WRF/PCE-ROMS-CICE

关键词： Arctic climate coupled model numerical simulation

Simulation of a Persistent Snow Storm over Southern China with a Regional Atmosphere-Ocean coupled model

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Advances in Atmospheric Sciences 2013年第2期30卷 425-447页

作者：廖治杰张耀存 School of Atmospheric Sciences Nanjing University

A regional atmosphere-ocean coupled model, RegCM3-POM, was developed by coupling the regional climate model （RegCM3） with the Princeton Ocean model （POM）. The performance of RegCM3-POM in simulating a persistent snow storm over southern China and the impact of the Madden Julian oscillation （MJO） on this persistent snow storm were investigated. Compared with the stand-alone RegCM3, the coupled model performed better at reproducing the spatial-temporal evolution and intensity of the precipitation episodes. The power spectral analysis indicated that the coupled model successfully captured the dominant period between 30 and 60 days in the precipitation field, leading to a notable improvement in simulating the magnitude of intraseasonal precipitation variation, and further in enhancing the intensity of the simulated precipitation. These improvements were mainly due to the well-simulated low-frequency oscillation center and its eastward propagation characteristics in each MJO phase by RegCM3-POM, which improved the simulations of MJO-related low-frequency vertical motions, water vapor transport, and the deep inversion layer that can directly influence the precipitation event and that further improved the simulated MJOprecipitation relationship. Analysis of the phase relationship between convection and SST indicated that RegCM3-POM exhibits a near-quadrature relation between the simulated convection and SST anomalies, which was consistent with the observations. However, such a near-quadrature relation was not as significant when the stand-alone RegCM3 was used. This difference indicated that the inherent coupled feedback process between the ocean and atmosphere in RegCM3-POM played an important part in reproducing the features of the MJO that accompanied the snow storm.

关键词： RegCM3 POM coupled model snow storm Madden Julian oscillation

ENSO Phase-Locking in an Ocean-Atmosphere coupled model FGCM-1.0

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Advances in Atmospheric Sciences 2007年第5期24卷 833-844页

作者：郑伟鹏俞永强 State Key Laboratory of Numerical modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029 Graduate University of the Chinese Academy of SciencesBeijing 100049 State Key Laboratory of Numerical modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029

The mean climatology and the basic characteristics of the ENSO cycle simulated by a coupled model FGCM-1.0 are investigated in this study. Although with some common model biases as in other directly coupled models, FGCM-1.0 is capable of producing the interannual variability of the tropical Pacific, such as the ENSO phenomenon. The mechanism of the ENSO events in the coupled model can be explained by “delayed oscillator” and “recharge-discharge” hypotheses. Compared to the observations, the simulated ENSO events show larger amplitude with two distinctive types of phase-locking： one with its peak phase-locked to boreal winter and the other to boreal summer. These two types of events have a similar frequency of occurrence, but since the second type of event is seldom observed, it may be related to the biases of the coupled model. Analysis show that the heat content anomalies originate from the central south Pacific in the type of events peaking in boreal summer, which can be attributed to a different background climatology from the normal events. The mechanisms of their evolutions are also discussed.

关键词： ENSO phase-locking coupled model

A Time-Domain coupled model for Nonlinear Wave Forces on A Fixed Box-Shaped Ship in A Harbor

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China Ocean Engineering 2010年第1期24卷 41-56页

作者：王大国邹志利谭国焕刘霞 Center for Material Failure modeling Research Dalian University The State Key Laboratory of Coastal and Offshore Engineering Department of Civil EngineeringDalian University of Technology Department of Civil and Structural Engineering The University of Hong Kong

A 2-D time-domain numerical coupled model is developed to obtain an efficient method for nonlinear wave forces on a fixed box-shaped ship in a harbor. The domain is divided into an inner domain and an outer domain. The inner domain is the area beneath the ship and the flow is described by the simplified Euler equations. The other area is the outer domain and the flow is defined by the higher-order Boussinesq equations in order to consider the nonlinearity of the wave motions. Along the interface boundaries between the inner domain and the outer domain, the volume flux is assumed to be continuous and the wave pressures are equal. Relevant physical experiment is conducted to validate the present model. It is shown that the numerical results agree with the experimental data. Compared with the coupled model with the flow in the inner domain governed by the Laplace equation, the present coupled model is more efficient and its solution procedure is more simple, which is particularly useful for the study on the effect of the nonlinear wave forces on a fixed box-shaped ship in a large harbor.

关键词： coupled model wave forces Boussinesq equations Euler equations

Assessment of earthquake-induced landslide hazard zoning using the physics-environmental coupled model

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Journal of Mountain Science 2023年第9期20卷 2644-2664页

作者： ZENG Ying ZHANG Ying-bin LIU Jing XU Pei-yi ZHU Hui YU Hai-hong HE Yun-yong Department of Geotechnical Engineering School of Civil EngineeringSouthwest Jiaotong UniversityChengdu 610031China CREC Sichuan Eco-City Investment Co. Ltd.Chengdu 420562China Sichuan Highway Planning SurveyDesign and Research Institute Ltd.Chengdu 610041China

In order to prevent and mitigate disasters,it is crucial to immediately and properly assess the spatial distribution of landslide hazards in the earthquake-affected ***,there are primarily two categories of assessment techniques:the physical mechanism-based method(PMBM),which considers the landslide dynamics and has the advantages of effectiveness and proactivity;the environmental factor-based method(EFBM),which integrates the environmental conditions and has high *** order to obtain the spatial distribution of landslide hazards in the affected area with near realtime and high accuracy,this study proposed to combine the PMBM based on Newmark method with EFBM to form Newmark-Information value model(N-IV),Newmark-Logic regression model(N-LR)and Newmark-Support Vector Machine model(N-SVM)for seismic landslide hazard assessment on the Ludian Mw 6.2 earthquake in *** predicted spatial hazard distribution was compared with the actual cataloged landslide inventory,and frequency ratio(FR),and area under the curve(AUC)metrics were used to verify the model's plausibility,performance,and *** to the findings,the model's accuracy is ranked as follows:N-SVM>N-LR>N-IV>*** an AUC value of 0.937,the linked N-SVM was discovered to have the best *** research results indicate that the physics-environmental coupled model(PECM)exhibits accuracy gains of 46.406%(N-SVM),30.625%(N-LR),and 22.816%(N-IV)when compared to the conventional Newmark *** shows varied degrees of improvement from 2.577%to 12.446%when compared to the single *** study also uses the Ms 6.8 Luding earthquake to evaluate the model,showcasing its trustworthy in forecasting power and steady *** the suggested PECM in this study can adapt to complicated earthquake-induced landslides situations,it aims to serve as a reference for future research in a similar field,as well as to help with emergency planning and response in earthquakepro

关键词： Earthquake-induced landslides Newmark method coupled model Ludian earthquake Landslide distribution

Seepage-Stress-Damage coupled model of Coal Under Geo-Stress Influence

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Computers, Materials & Continua 2018年第1期54卷 43-59页

作者： Yi Xue Faning Dang Rongjian Li Liuming Fan Qin Hao Lin Mu Yuanyuan Xia State Key Laboratory Base of Eco-Hydraulic Engineering in Arid Areas Xi’an University of TechnologyXi’an 710048China Institute of Geotechnical Engineering Shaanxi Provincial Key Laboratory of Loess Mechanics and EngineeringXi’an University of TechnologyXi’an 710048China Department of Civil Engineering Henan Vocational College of Water Conservancy and EnvironmentZhengzhou 450011China

In the seepage-stress-damage coupled process,the mechanical properties and seepage characteristics of coal are distinctly different between pre-peak stage and post-peak *** difference is mainly caused by damage of ***,in the process of seepage and stress analysis of coal under the influence of excavation or mining,we need to consider the weakening of mechanical properties and the development of fractures of damaged *** on this understanding,this paper analyzes the influence of damage on mechanics and seepage behavior of coal.A coupled model is established to analyze the seepage-stress-damage coupled process of *** model implemented into COMSOL and MATLAB software to realize the numerical *** examples are adopted to verify the correctness of the model and some useful conclusions are *** numerical model establishes the relationship between microcosmic damage evolution and macroscopical fracture and simulates the whole process of coal from microcosmic damage to macroscopical fracture,and the dynamic simulation of fluid flow in this *** provides a numerical tool for further research on the seepage-stress-damage analysis.

关键词： Permeability porosity gas pressure damage coupled model

Impact of the Time Scale of model Sensitivity Response on coupled model Parameter Estimation

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Advances in Atmospheric Sciences 2017年第11期34卷 1346-1357页

作者： chang liu shaoqing zhang shan li zhengyu liu Center for Climate Research and Department of Atmospheric and Oceanic Sciences University of Wisconsin -- Madison Madison W153706 USA

That a model has sensitivity responses to parameter uncertainties is a key concept in implementing model parameter es- timation using filtering theory and methodology. Depending on the nature of associated physics and characteristic variability of the fluid in a coupled system, the response time scales of a model to parameters can be different, from hourly to decadal. Unlike state estimation, where the update frequency is usually linked with observational frequency, the update frequency for parameter estimation must be associated with the time scale of the model sensitivity response to the parameter being esti- mated. Here, with a simple coupled model, the impact of model sensitivity response time scales on coupled model parameter estimation is studied. The model includes characteristic synoptic to decadal scales by coupling a long-term varying deep ocean with a slow-varying upper ocean forced by a chaotic atmosphere. Results show that, using the update frequency deter- mined by the model sensitivity response time scale, both the reliability and quality of parameter estimation can be improved significantly, and thus the estimated parameters make the model more consistent with the observation. These simple model results provide a guideline for when real observations are used to optimize the parameters in a coupled general circulation model for improving climate analysis and prediction initialization.

关键词： coupled model parameter estimation time scale of model sensitivity

A 3-D Time-Domain coupled model for Nonlinear Waves Acting on A Box-Shaped Ship Fixed in A Harbor

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China Ocean Engineering 2011年第3期25卷 441-456页

作者：王大国邹志利 THAM Leslie George Center for Material Failure modeling Research Dalian University The State Key Laboratory of Coastal and Offshore Engineering Department of Civil EngineeringDalian University of Technology Department of Civil and Structural Engineering The University of Hong Kong

A 3-D time-domain numerical coupled model is developed to obtain an efficient method for nonlinear waves acting on a box-shaped ship fixed in a harbor. The domain is divided into the inner domain and the outer domain. The inner domain is the area beneath the ship and the flow is described by the simplified Euler equations. The remaining area is the outer domain and the flow is defined by the higher-order Boussinesq equations in order to consider the nonlinearity of the wave motions. Along the interface boundaries between the inner domain and the outer domain, the volume flux is assumed to be continuous and the wave pressures are equal. Relevant physical experiment is conducted to validate the present mode/and it is shown that the numerical results agree with the experimental data. Compared the coupled model with the flow in the inner domain governed by the Laplace equation, the present coupled model is more efficient and its solution procedure is simpler, which is particularly useful for the study on the effect of the nonlinear waves acting on a fixed box-shaped ship in a large harbor.

关键词： nonlinear waves coupled model Boussinesq equations Euler equations