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Simulation Method and Feature Analysis of Shutdown Pressure Evolution During Multi-Cluster Fracturing Stimulation
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作者 Huaiyin He Longqing Zou +5 位作者 Yanchao Li Yixuan Wang Junxiang Li Huan Wen Bei Chang Lijun Liu 《Energy Engineering》 EI 2024年第1期111-123,共13页
Multistage multi-cluster hydraulic fracturing has enabled the economic exploitation of shale reservoirs,but the interpretation of hydraulic fracture parameters is challenging.The pressure signals after pump shutdown a... Multistage multi-cluster hydraulic fracturing has enabled the economic exploitation of shale reservoirs,but the interpretation of hydraulic fracture parameters is challenging.The pressure signals after pump shutdown are influenced by hydraulic fractures,which can reflect the geometric features of hydraulic fracture.The shutdown pressure can be used to interpret the hydraulic fracture parameters in a real-time and cost-effective manner.In this paper,a mathematical model for shutdown pressure evolution is developed considering the effects of wellbore friction,perforation friction and fluid loss in fractures.An efficient numerical simulation method is established by using the method of characteristics.Based on this method,the impacts of fracture half-length,fracture height,opened cluster and perforation number,and filtration coefficient on the evolution of shutdown pressure are analyzed.The results indicate that a larger fracture half-length may hasten the decay of shutdown pressure,while a larger fracture height can slow down the decay of shutdown pressure.A smaller number of opened clusters and perforations can significantly increase the perforation friction and decrease the overall level of shutdown pressure.A larger filtration coefficient may accelerate the fluid filtration in the fracture and hasten the drop of the shutdown pressure.The simulation method of shutdown pressure,as well as the analysis results,has important implications for the interpretation of hydraulic fracture parameters. 展开更多
关键词 Multistage multi-cluster hydraulic fracturing pump shutdown pressure feature analysis numerical simulation
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Thermal stress simulation analysis of aerospace optical fibers and connectors and related extensions to high-speed railway area
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作者 Feng Zhou Siyuan Yu +3 位作者 Zeren Gao Jie Kan Hao Xu Mengjie Liu 《High-Speed Railway》 2024年第2期122-132,共11页
Aerospace optical cables and fiber-optic connectors have numerous advantages(e.g.,low loss,wide transmission frequency band,large capacity,light weight,and excellent resistance to electromagnetic interference).They ca... Aerospace optical cables and fiber-optic connectors have numerous advantages(e.g.,low loss,wide transmission frequency band,large capacity,light weight,and excellent resistance to electromagnetic interference).They can achieve optical communication interconnections and high-speed bidirectional data transmission between optical terminals and photodetectors in space,ensuring the stability and reliability of data transmission during spacecraft operations in orbit.They have become essential components in high-speed networking and optically interconnected communications for spacecrafts.Thermal stress simulation analysis is important for evaluating the temperature stress concentration phenomenon resulting from temperature fluctuations,temperature gradients,and other factors in aerospace optical cables and connectors under the combined effects of extreme temperatures and vacuum environments.Considering this,advanced optical communication technology has been widely used in high-speed railway communication networks to transmit safe,stable and reliable signals,as high-speed railway optical communication in special areas with extreme climates,such as cold and high-temperature regions,requires high-reliability optical cables and connectors.Therefore,based on the finite element method,comprehensive comparisons were made between the thermal distributions of aerospace optical cables and J599III fiber optic connectors under different conditions,providing a theoretical basis for evaluating the performance of aerospace optical cables and connectors in space environments and meanwhile building a technical foundation for potential optical communication applications in the field of high-speed railways. 展开更多
关键词 Aerospace optical fiber Aerospace optic connector simulation analysis
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Simulation Analysis of Deformation Control for Magnetic Soft Medical Robots
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作者 Jingxi Wang Baoyu Liu +2 位作者 Edmond Q.Wu Jin Ma Ping Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期794-796,共3页
Dear Editor,This letter presents a biocompatible cross-shaped magnetic soft robot and investigates its deformation mode control strategy through COMSOL modeling and simulation.Magnetic soft robots offer novel avenues ... Dear Editor,This letter presents a biocompatible cross-shaped magnetic soft robot and investigates its deformation mode control strategy through COMSOL modeling and simulation.Magnetic soft robots offer novel avenues for precise treatment within intricate regions of the human body. 展开更多
关键词 ROBOT simulation COMSOL
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Analysis of debris flow control effect and hazard assessment in Xinqiao Gully,Wenchuan M_(s)8.0 earthquake area based on numerical simulation 被引量:1
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作者 Chang Yang Yong-bo Tie +3 位作者 Xian-zheng Zhang Yan-feng Zhang Zhi-jie Ning Zong-liang Li 《China Geology》 CAS CSCD 2024年第2期248-263,共16页
Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the eff... Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events. 展开更多
关键词 Landslide Debris flow Hazard assessment Numerical simulation OpenLISEM Prevention and control project Wenchuan M_(s)8.0 earthquake Xinqiao Gully Sichuan province Geological hazards survey engineering
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Genetic Analysis of Structural Styles in the Makran Accretionary Wedge–Insight from Physical Simulations
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作者 SHAO Longfei YU Fusheng +6 位作者 GONG Jianming LIAO Jing YU Zhifeng TANG Liang CHEN Jiangong WANG Yuefeng NENG Yuan 《Journal of Ocean University of China》 CAS CSCD 2024年第1期157-172,共16页
The Makran accretionary wedge has the smallest subduction angle among any accretionary prism in the world. The factors controlling the spacing and morphological development of its deep thrust faults, as well as the fo... The Makran accretionary wedge has the smallest subduction angle among any accretionary prism in the world. The factors controlling the spacing and morphological development of its deep thrust faults, as well as the formation mechanism of shallow normal faults, remain unclear. Meanwhile, the factors affecting the continuity of plane faults must be comprehensively discussed. Clarifying the development characteristics and deformation mechanisms of the Makran accretionary wedge is crucial to effectively guide the exploration of gas hydrate deposits in the area. This study aims to interpret seismic data to identify typical structures in the Makran accretionary wedge, including deep imbricate thrust faults, shallow and small normal faults, wedge-shaped piggyback basins, mud diapirs with fuzzy and disorderly characteristics of reflection, décollements with a northward tilt of 1° – 2°, and large seamounts. Physical simulation-based experiments are performed to comprehensively analyze the results of the plane, section, and slices of the wedge. Results reveal that the distances between and shapes of thrust faults in the deep parts of the Makran accretionary wedge are controlled by the bottom décollement. The uplift of the thrust fault-related folds and the upwelling of the mud diapirs primarily contribute to the formation of small normal faults in the shallow part of the area. The mud diapirs originate from plastic material at the bottom, while those that have developed in the area near the trench are larger. Seamounts and mud diapirs break the continuity of fault plane distribution. 展开更多
关键词 Makran accretionary wedge structural styles faults distribution physical simulation
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Effects of Different Concentrations of Sulfate Ions on Carbonate Crude Oil Desorption:Experimental Analysis and Molecular Simulation
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作者 Nannan Liu Hengchen Qi +1 位作者 Hui Xu Yanfeng He 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1731-1741,共11页
Low salinity water containing sulfate ions can significantly alter the surface wettability of carbonate rocks.Nevertheless,the impact of sulfate concentration on the desorption of oil film on the surface of carbonate ... Low salinity water containing sulfate ions can significantly alter the surface wettability of carbonate rocks.Nevertheless,the impact of sulfate concentration on the desorption of oil film on the surface of carbonate rock is still unknown.This study examines the variations in the wettability of the surface of carbonate rocks in solutions containing varying amounts of sodium sulfate and pure water.The problem is addressed in the framework of molecular dynamics simulation(Material Studio software)and experiments.The experiment’s findings demonstrate that sodium sulfate can increase the rate at which oil moisture is turned into water moisture.The final contact angle is smaller than that of pure water.The results of the simulations show that many water molecules travel down the water channel under the influence of several powerful forces,including the electrostatic force,the van der Waals force and hydrogen bond,crowding out the oil molecules on the calcite’s surface and causing the oil film to separate.The relative concentration curve of water and oil molecules indicates that the separation rate of the oil film on the surface of calcite increases with the number of sulfate ions. 展开更多
关键词 Carbonate rocks WETTABILITY sulfate ions CONCENTRATION molecular simulation DESORPTION
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Multi-scenario Simulation and Spatial-temporal Analysis of LUCC in China's Coastal Zone Based on Coupled SD-FLUS Model
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作者 HOU Xiyong SONG Baiyuan +2 位作者 ZHANG Xueying WANG Xiaoli LI Dong 《Chinese Geographical Science》 SCIE CSCD 2024年第4期579-598,共20页
Increased human activities in China's coastal zone have resulted in the depletion of ecological land resources.Thus,conducting current and future multi-scenario simulation research on land use and land cover chang... Increased human activities in China's coastal zone have resulted in the depletion of ecological land resources.Thus,conducting current and future multi-scenario simulation research on land use and land cover change(LUCC)is crucial for guiding the healthy and sustainable development of coastal zones.System dynamic(SD)-future land use simulation(FLUS)model,a coupled simulation model,was developed to analyze land use dynamics in China's coastal zone.This model encompasses five scenarios,namely,SSP1-RCP2.6(A),SSP2-RCP4.5(B),SSP3-RCP4.5(C),SSP4-RCP4.5(D),and SSP5-RCP8.5(E).The SD model simulates land use demand on an annual basis up to the year 2100.Subsequently,the FLUS model determines the spatial distribution of land use for the near term(2035),medium term(2050),and long term(2100).Results reveal a slowing trend in land use changes in China's coastal zone from 2000–2020.Among these changes,the expansion rate of construction land was the highest and exhibited an annual decrease.By 2100,land use predictions exhibit high accuracy,and notable differences are observed in trends across scenarios.In summary,the expansion of production,living,and ecological spaces toward the sea remains prominent.Scenario A emphasizes reduced land resource dependence,benefiting ecological land protection.Scenario B witnesses an intensified expansion of artificial wetlands.Scenario C sees substantial land needs for living and production,while Scenario D shows coastal forest and grassland shrinkage.Lastly,in Scenario E,the conflict between humans and land intensifies.This study presents pertinent recommendations for the future development,utilization,and management of coastal areas in China.The research contributes valuable scientific support for informed,long-term strategic decision making within coastal regions. 展开更多
关键词 land use and land cover change(LUCC) multi-scenario simulation system dynamic-future land use simulation(SD-FLUS)model SSP-RCP scenarios model coupling China's coastal zone
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Effects of Initial and Boundary Conditions on Heavy Rainfall Simulation over the Yellow Sea and the Korean Peninsula:Comparison of ECMWF and NCEP Analysis Data Effects and Verification with Dropsonde Observation
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作者 Jiwon HWANG Dong-Hyun CHA +2 位作者 Donghyuck YOON Tae-Young GOO Sueng-Pil JUNG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1787-1803,共17页
This study evaluated the simulation performance of mesoscale convective system(MCS)-induced precipitation,focusing on three selected cases that originated from the Yellow Sea and propagated toward the Korean Peninsula... This study evaluated the simulation performance of mesoscale convective system(MCS)-induced precipitation,focusing on three selected cases that originated from the Yellow Sea and propagated toward the Korean Peninsula.The evaluation was conducted for the European Centre for Medium-Range Weather Forecasts(ECMWF)and National Centers for Environmental Prediction(NCEP)analysis data,as well as the simulation result using them as initial and lateral boundary conditions for the Weather Research and Forecasting model.Particularly,temperature and humidity profiles from 3D dropsonde observations from the National Center for Meteorological Science of the Korea Meteorological Administration served as validation data.Results showed that the ECMWF analysis consistently had smaller errors compared to the NCEP analysis,which exhibited a cold and dry bias in the lower levels below 850 hPa.The model,in terms of the precipitation simulations,particularly for high-intensity precipitation over the Yellow Sea,demonstrated higher accuracy when applying ECMWF analysis data as the initial condition.This advantage also positively influenced the simulation of rainfall events on the Korean Peninsula by reasonably inducing convective-favorable thermodynamic features(i.e.,warm and humid lower-level atmosphere)over the Yellow Sea.In conclusion,this study provides specific information about two global analysis datasets and their impacts on MCS-induced heavy rainfall simulation by employing dropsonde observation data.Furthermore,it suggests the need to enhance the initial field for MCS-induced heavy rainfall simulation and the applicability of assimilating dropsonde data for this purpose in the future. 展开更多
关键词 initial conditions dropsonde heavy rainfall forecast global model analysis evaluation
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Physics-based seismic analysis of ancient wood structure:fault-to-structure simulation
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作者 Ba Zhenning Fu Jisai +3 位作者 Wang Fangbo Liang Jianwen Zhang Bin Zhang Long 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期727-740,共14页
Based on the domain reduction method,this study employs an SEM-FEM hybrid workflow which integrates the advantages of the spectral element method(SEM)for flexible and highly efficient simulation of seismic wave propag... Based on the domain reduction method,this study employs an SEM-FEM hybrid workflow which integrates the advantages of the spectral element method(SEM)for flexible and highly efficient simulation of seismic wave propagation in a three-dimensional(3D)regional-scale geophysics model and the finite element method(FEM)for fine simulation of structural response including soil-structure interaction,and performs a physics-based simulation from initial fault rupture on an ancient wood structure.After verification of the hybrid workflow,a large-scale model of an ancient wood structure in the Beijing area,The Tower of Buddhist Incense,is established and its responses under the 1665 Tongxian earthquake and the 1730 Yiheyuan earthquake are simulated.The results from the simulated ground motion and seismic response of the wood structure under the two earthquakes demonstrate that this hybrid workflow can be employed to efficiently provide insight into the relationships between geophysical parameters and the structural response,and is of great significance toward accurate input for seismic simulation of structures under specific site and fault conditions. 展开更多
关键词 spectral element method finite element method fault-to-structure simulation physical model domain reduction method
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Imaging simulation and analysis of attitude jitter effect on topographic mapping for lunar orbiter stereo optical cameras
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作者 CHEN Chen TONG Xiao-Hua +4 位作者 LIU Shi-Jie YE Zhen HUANG Chao-Wei WU Hao ZHANG Han 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2024年第5期722-730,共9页
The geometric accuracy of topographic mapping with high-resolution remote sensing images is inevita-bly affected by the orbiter attitude jitter.Therefore,it is necessary to conduct preliminary research on the stereo m... The geometric accuracy of topographic mapping with high-resolution remote sensing images is inevita-bly affected by the orbiter attitude jitter.Therefore,it is necessary to conduct preliminary research on the stereo mapping camera equipped on lunar orbiter before launching.In this work,an imaging simulation method consid-ering the attitude jitter is presented.The impact analysis of different attitude jitter on terrain undulation is conduct-ed by simulating jitter at three attitude angles,respectively.The proposed simulation method is based on the rigor-ous sensor model,using the lunar digital elevation model(DEM)and orthoimage as reference data.The orbit and attitude of the lunar stereo mapping camera are simulated while considering the attitude jitter.Two-dimensional simulated stereo images are generated according to the position and attitude of the orbiter in a given orbit.Experi-mental analyses were conducted by the DEM with the simulated stereo image.The simulation imaging results demonstrate that the proposed method can ensure imaging efficiency without losing the accuracy of topographic mapping.The effect of attitude jitter on the stereo mapping accuracy of the simulated images was analyzed through a DEM comparison. 展开更多
关键词 topographic mapping lunar orbiter stereo camera attitude jitter imaging simulation digital elevation model
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Finite Element Simulation Analysis of a Novel 3D-FRSPA for Crawling Locomotion
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作者 Bingzhu Wang Xiangrui Ye 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1401-1425,共25页
A novel three-dimensional-fiber reinforced soft pneumatic actuator(3D-FRSPA)inspired by crab claw and human hand structure that can bend and deform independently in each segment is proposed.It has an omni-directional ... A novel three-dimensional-fiber reinforced soft pneumatic actuator(3D-FRSPA)inspired by crab claw and human hand structure that can bend and deform independently in each segment is proposed.It has an omni-directional bending configuration,and the fibers twined symmetrically on both sides to improve the bending performance of FRSPA.In this paper,the static and kinematic analysis of 3D-FRSPA are carried out in detail.The effects of fiber,pneumatic chamber and segment length,and circular air chamber radius of 3D-FRSPA on the mechanical performance of the actuator are discussed,respectively.The soft mobile robot composed of 3D-FRSPA has the ability to crawl.Finally,the crawling processes of the soft mobile robot on different road conditions are studied,respectively,and the motion mechanism of the mobile actuator is shown.The numerical results show that the soft mobile robots have a good comprehensive performance,which verifies the correctness of the proposedmodel.This work shows that the proposed structures have great potential in complex road conditions,unknown space detection and other operations. 展开更多
关键词 3D-FRSPA bionic structure theoretical modeling crawling application obstacle avoidance analysis numerical investigation
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Numerical Simulation of Heat Transfer Process and Heat Loss Analysis in Siemens CVD Reduction Furnaces
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作者 Kunrong Shen Wanchun Jin Jin Wang 《Frontiers in Heat and Mass Transfer》 EI 2024年第5期1361-1379,共19页
The modified Siemens method is the dominant process for the production of polysilicon,yet it is characterised by high energy consumption.Two models of laboratory-grade Siemens reduction furnace and 12 pairs of rods in... The modified Siemens method is the dominant process for the production of polysilicon,yet it is characterised by high energy consumption.Two models of laboratory-grade Siemens reduction furnace and 12 pairs of rods industrial-grade Siemens chemical vapor deposition(CVD)reduction furnace were established,and the effects of factors such as the diameter of silicon rods,the surface temperature of silicon rods,the air inlet velocity and temperature on the heat transfer process inside the reduction furnace were investigated by numerical simulation.The results show that the convective and radiant heat losses in the furnace increased with the diameter of the silicon rods.Furthermore,the radiant heat loss of the inner and outer rings of silicon rods was inconsistent for the industrial-grade reduction furnace.As the surface temperature of the silicon rods increases,the convective heat loss in the furnace increases,while the radiative heat loss remains relatively constant.When the inlet temperature and inlet velocity increase,the convective heat loss decreases,while the radiant heat loss remains relatively constant.Furthermore,the furnace wall surface emissivity increases,resulting in a significant increase in the amount of radiant heat loss in the furnace.In practice,this can be mitigated by polishing or adding coatings to reduce the furnace wall surface emissivity. 展开更多
关键词 Modified siemens method polysilicon reduction furnace energy consumption numerical simulation
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Numerical Simulation Analysis of Welded Joints in Arch Ribs of Large Span Steel Pipe Arch Bridges
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作者 Deer He Nianchun Deng Xiuning Peng 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第3期19-30,共12页
In order to study the residual stress distribution law of welded joints of arch ribs of large-span steel pipe concrete arch bridges,numerical simulation of temperature,stress and strain fields based on ABAQUS for weld... In order to study the residual stress distribution law of welded joints of arch ribs of large-span steel pipe concrete arch bridges,numerical simulation of temperature,stress and strain fields based on ABAQUS for welded joints of arch-ribbed steel tubes using 7-,8-and 9-layer welds is carried out and its accuracy is demonstrated.The steel pipe welding temperature changes,residual stress distribution,different processes residual stress changes in the law,the prediction of post-weld residual stress distribution and deformation are studied in this paper.The results show that the temperature field values and test results are more consistent with the accuracy of numerical simulation of welding,the welding process is mainly in the form of heat transfer;Residual high stresses are predominantly distributed in the Fusion zone(FZ)and Heat-affected zone(HAZ),with residual stress levels tending to decrease from the center of the weld along the axial path,the maximum stress appears in the FZ and HAZ junction;The number of welding layers has an effect on the residual stress distribution,the number of welding layers increases,the residual stress tends to decrease,while the FZ and HAZ high stress area range shrinks;Increasing the number of plies will increase the amount of residual distortion. 展开更多
关键词 steel pipe and concrete arch bridge arch rib multi-pass welding residual stress numerical simulation
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Modeling,Simulation,and Risk Analysis of Battery Energy Storage Systems in New Energy Grid Integration Scenarios
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作者 Xiaohui Ye Fucheng Tan +4 位作者 Xinli Song Hanyang Dai Xia Li Shixia Mu Shaohang Hao 《Energy Engineering》 EI 2024年第12期3689-3710,共22页
Energy storage batteries can smooth the volatility of renewable energy sources.The operating conditions during power grid integration of renewable energy can affect the performance and failure risk of battery energy s... Energy storage batteries can smooth the volatility of renewable energy sources.The operating conditions during power grid integration of renewable energy can affect the performance and failure risk of battery energy storage system(BESS).However,the current modeling of grid-connected BESS is overly simplistic,typically only considering state of charge(SOC)and power constraints.Detailed lithium(Li)-ion battery cell models are computationally intensive and impractical for real-time applications and may not be suitable for power grid operating conditions.Additionally,there is a lack of real-time batteries risk assessment frameworks.To address these issues,in this study,we establish a thermal-electric-performance(TEP)coupling model based on a multitime scale BESS model,incorporating the electrical and thermal characteristics of Li-ion batteries along with their performance degradation to achieve detailed simulation of grid-connected BESS.Additionally,considering the operating characteristics of energy storage batteries and electrical and thermal abuse factors,we developed a battery pack operational riskmodel,which takes into account SOCand charge-discharge rate(Cr),using amodified failure rate to represent the BESS risk.By integrating detailed simulation of energy storage with predictive failure risk analysis,we obtained a detailed model for BESS risk analysis.This model offers a multi-time scale integrated simulation that spans month-level energy storage simulation times,day-level performance degradation,minutescale failure rate,and second-level BESS characteristics.It offers a critical tool for the study of BESS.Finally,the performance and risk of energy storage batteries under three scenarios—microgrid energy storage,wind power smoothing,and power grid failure response—are simulated,achieving a real-time state-dependent operational risk analysis of the BESS. 展开更多
关键词 Grid-connected battery energy storage system thermal-electric-performance coupling model operational risk model failure rate risk analysis
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Numerical Simulation-Based Analysis of the Impact of Overloading on Segmentally Assembled Bridges
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作者 Donghui Ma Wenqi Wu +4 位作者 Yuan Li Lun Zhao Yingchun Cai Pan Guo Shaolin Yang 《Structural Durability & Health Monitoring》 EI 2024年第5期663-681,共19页
Segmentally assembled bridges are increasinglyfinding engineering applications in recent years due to their unique advantages,especially as urban viaducts.Vehicle loads are one of the most important variable loads acti... Segmentally assembled bridges are increasinglyfinding engineering applications in recent years due to their unique advantages,especially as urban viaducts.Vehicle loads are one of the most important variable loads acting on bridge structures.Accordingly,the influence of overloaded vehicles on existing assembled bridge structures is an urgent concern at present.This paper establishes thefinite element model of the segmentally assembled bridge based on ABAQUS software and analyzes the influence of vehicle overload on an assembled girder bridge struc-ture.First,afinite element model corresponding to the target bridge is established based on ABAQUS software,and the load is controlled to simulate vehicle movement in each area of the traveling zone at different times.Sec-ond,the key cross-sections of segmental girder bridges are monitored in real time based on the force character-istics of continuous girder bridges,and they are compared with the simulation results.Finally,a material damage ontology model is introduced,and the structural damage caused by different overloading rates is compared and analyzed.Results show that thefinite element modeling method is accurate by comparing with on-site measured data,and it is suitable for the numerical simulation of segmental girder bridges;Dynamic sensors installed at 1/4L,1/2L,and 3/4L of the segmental girder main beams could be used to identify the dynamic response of segmental girder bridges;The bottom plate of the segmental girder bridge is mostly damaged at the position where the length of the precast beam section changes and the midspan position.With the increase in load,damage in the direction of the bridge develops faster than that in the direction of the transverse bridge.Thefindings of this study can guide maintenance departments in the management and maintenance of bridges and vehicles. 展开更多
关键词 Segmentally assembled bridge dynamic response moving loads OVERLOADING structural damage finite element analysis
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Energy and Exergy Analysis of Pyramid-Type Solar Still Coupled with Magnetic and Electrical Effects by UsingMatlab Simulation
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作者 Karrar A.Hammoodi Hayder A.Dhahad +1 位作者 Wissam H.Alawee Z.M.Omara 《Frontiers in Heat and Mass Transfer》 EI 2024年第1期217-262,共46页
In the face of an escalating global water crisis,countries worldwide grapple with the crippling effects of scarcity,jeopardizing economic progress and hindering societal advancement.Solar energy emerges as a beacon of... In the face of an escalating global water crisis,countries worldwide grapple with the crippling effects of scarcity,jeopardizing economic progress and hindering societal advancement.Solar energy emerges as a beacon of hope,offering a sustainable and environmentally friendly solution to desalination.Solar distillation technology,harnessing the power of the sun,transforms seawater into freshwater,expanding the availability of this precious resource.Optimizing solar still performance under specific climatic conditions and evaluating different configurations is crucial for practical implementation and widespread adoption of solar energy.In this study,we conducted theoretical investigations on three distinct solar still configurations to evaluate their performance under Baghdad’s climatic conditions.The solar stills analyzed include the passive solar still,themodified solar still coupled with a magnetic field,and themodified solar still coupled with bothmagnetic and electrical fields.The results proved that the evaporation heat transfer coefficient peaked at 14:00,reaching 25.05 W/m^(2).℃for the convention pyramid solar still(CPSS),32.33 W/m^(2).℃for the magnetic pyramid solar still(MPSS),and 40.98 W/m^(2).℃for elecro-magnetic pyramid solar still(EMPSS),highlighting their efficiency in converting solar energy to vapor.However,exergy efficiency remained notably lower,at 1.6%,5.31%,and 7.93%for the three still types,even as energy efficiency reached its maximum of 18.6%at 14:00 with a corresponding peak evaporative heat of 162.4 W/m^(2). 展开更多
关键词 Pyramid solar still solar desalination energy and exergy analysis innovative solar still technique theoretical study Matlab
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Furnace structure analysis for copper flash continuous smelting based on numerical simulation 被引量:7
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作者 汪金良 陈亚州 +1 位作者 张文海 张传福 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第12期3799-3807,共9页
According to the innate characteristic of four types of furnace, the copper flash continuous smelting (CFCS) furnace can be considered a synthetic reactor of two relatively independent processes: flash matte smelti... According to the innate characteristic of four types of furnace, the copper flash continuous smelting (CFCS) furnace can be considered a synthetic reactor of two relatively independent processes: flash matte smelting process (FMSP) and copper continuous converting process (CCCP). Then, the CFCS thermodynamic model was proposed by establishing the multi-phase equilibrium model of FMSP and the local-equilibrium model of CCCP, respectively, and by combining them through the smelting intermediates. Subsequently, the influences of the furnace structures were investigated using the model on the formation of blister copper, the Fe3O4 behavior, the copper loss in slag and the copper recovery rate. The results show that the type D furnace, with double flues and a slag partition wall, is an ideal CFCS reactor compared with the other three types furnaces. For CFCS, it is effective to design a partition wall in the furnace to make FMSP and CCCP perform in two relatively independent zones, respectively, and to make smelting gas and converting gas discharge from respective flues. 展开更多
关键词 furnace structure copper flash continuous smelting numerical simulation thermodynamic analysis
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Electromagnetic simulation and experimental analysis of microwave heaters for asphalt pavements 被引量:3
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作者 朱松青 张志胜 史泰龙 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期410-416,共7页
In order to study the thermoelectric efficiency of microwave heating and reproduction of asphalt pavements and the uniformity of reproduction temperature distribution, a waveguide excitation cavity is designed and app... In order to study the thermoelectric efficiency of microwave heating and reproduction of asphalt pavements and the uniformity of reproduction temperature distribution, a waveguide excitation cavity is designed and applied to the structural design of a microwave heater. The structural sizes of the incentive cavities are determined based on the waveguide transmission line theory. Using IE3D software, electromagnetic simulations are respectively carried out in four different situations, including the distances between the magnetron probes (antennas) and a short-circuit board, different horn electric lengths and aperture sizes, different dielectric properties of the asphalt mixture, and the distances between the asphalt surface and the mouth cavity. The results show that, when the distance between the magnetron probe and the short-circuit board is 32.5 ram, it is the best installation site; reduction of aerial length is the main factor in improving the heating uniformity. When the aggregate is limestone, the best heating effect can be produced. Maximum radiation efficiency can be realized by adjusting the space between the heater radiation port and the asphalt pavement. The experimental results of asphalt mixture heating in four different situations have a substantial agreement with the simulation results, which confirms that the developed microwave heater can achieve better impedance matching, thus improving the quality and efficiency of heating regeneration. 展开更多
关键词 microwave heater excitation cavity structural design electromagnetic simulation temperature distribution experimental analysis
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Numerical simulation and physical analysis for dynamic behaviors of P/M TiAl alloy in hot-packed forging process 被引量:2
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作者 张伟 刘咏 +1 位作者 王丽 刘彬 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期901-906,共6页
The hot forging of large-scale P/M TiAl alloy billet deformation was investigated based on a joint application of Deform-3D-based numerical simulation and physical simulation techniques.The temperature dependence on t... The hot forging of large-scale P/M TiAl alloy billet deformation was investigated based on a joint application of Deform-3D-based numerical simulation and physical simulation techniques.The temperature dependence on the thermal and mechanical properties of the billet was considered and the optimum hot working temperature of packed TiAl alloy was 1150-1200 °C.Based on the simulation,the material flow and thermo mechanical field variables,such as stress,strain,and temperature distribution were obtained and the relationships of load—displacement and load—time were figured out.To verify the validity of the simulation results,the experiments were also carried out in a forging plant,and a pancake with diameter of 150 mm was obtained exhibiting a regular shape. 展开更多
关键词 TIAL hot packed forging numerical simulation physical simulation
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Interval Sampling Method for Steady-State Simulation Output Analysis
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作者 张鸿端 鲍居武 冯允成 《Journal of Beijing Institute of Technology》 EI CAS 1994年第1期18+8-17,共11页
A new algorithm namely the interval sampling method, applicable to the analysisof steady-state simulation output is proposed. This algorithm uses the time series analysisto carry out conrrelation analysis of the stead... A new algorithm namely the interval sampling method, applicable to the analysisof steady-state simulation output is proposed. This algorithm uses the time series analysisto carry out conrrelation analysis of the steady-state simulation output so as to obtain theobservation data which are actually uncorrelated in nature. On the basis of theseuncorrelated data gathered, some satisfactory deductions cam be made on the data under re search. A comparison between batch means method and the interval sampling method hasbeen performed by taking the M/M/l queuing system as an example. The results attestedthat the interval sampling method is mere accurate than the batch means method. 展开更多
关键词 simulation time series analysis correlation analysis/simulation output analysis
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