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Carbon Footprint and Economic Analysis of LNG-fueled Fishing Vessel Using Real Engine Performance Simulation
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作者 Momir Sjerić Maja Perčić +1 位作者 Ivana Jovanović Nikola Vladimir 《哈尔滨工程大学学报(英文版)》 2026年第1期259-276,共18页
Analysis of the environmental and economic performance of fishing vessels has received limited attention compared with other ship types despite their notable contribution to global greenhouse gas(GHG)emissions.This st... Analysis of the environmental and economic performance of fishing vessels has received limited attention compared with other ship types despite their notable contribution to global greenhouse gas(GHG)emissions.This study evaluates the carbon footprint(CF)and economic viability of a liquefied natural gas(LNG)-fueled fishing vessel,using real engine operation simulations to provide precise and dynamic evaluation of fuel consumption and GHG emissions.Operational profiles are obtained through the utilization of onboard monitoring systems,whereas engine performance is simulated using the 1D/0D AVL Boost^(TM)model.Life cycle assessment(LCA)is conducted to quantify the environmental impact,whereas life cycle cost assessment(LCCA)is performed to analyze the profitability of LNG as an alternative fuel.The potential impact of the future fuel price uncertainties is addressed using Monte Carlo simulations.The LCA findings indicate that LNG has the potential to reduce the CF of the vessel by 14%to 16%,in comparison to a diesel power system configuration that serves as the baseline scenario.The LCCA results further indicate that the total cost of an LNG-powered ship is lower by 9.5%-13.8%,depending on the share of LNG and pilot fuels.This finding highlights the potential of LNG to produce considerable environmental benefits while addressing economic challenges under diverse operational and fuel price conditions. 展开更多
关键词 1D/0D simulation Carbon footprint Fishing vessels Life cycle assessment Life cycle cost assessment Liquefied natural gas
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Dynamic impact simulation tests of deep roadways affected by high stress and fault slip 被引量:1
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作者 Qi Wang Yuncai Wang +3 位作者 Zhenhua Jiang Hongpu Kang Chong Zhang Bei Jiang 《International Journal of Mining Science and Technology》 2025年第4期519-537,共19页
As coal mining depth increases,the combined effects of high stress,mining stress,and fault structures make dynamic impact hazards more frequent.The reproduction of dynamic impact phenomena is basis for studying their ... As coal mining depth increases,the combined effects of high stress,mining stress,and fault structures make dynamic impact hazards more frequent.The reproduction of dynamic impact phenomena is basis for studying their occurrence patterns and control mechanisms.Physical simulation test represents an efficacious methodology.However,there is currently a lack of simulation devices that can effectively simulate two types of dynamic impact phenomena,including high stress and fault slip dynamic impact.To solve aforementioned issues,the physical simulation test system for dynamic impact in deep roadways developed by authors is employed to carry out comparative tests of high stress and fault slip dynamic impact.The phenomena of high stress and fault slip dynamic impact are reproduced successfully.A comparative analysis is conducted on dynamic phenomena,stress evolution,roadway deformation,and support force.The high stress dynamic impact roadway instability mode,which is characterized by the release of high energy accompanied by symmetric damage,and the fault slip dynamic impact roadway instability mode,which is characterized by the propagation of unilateral stress waves accompanied by asymmetric damage,are clarified.On the basis,the differentiated control concepts for different types of dynamic impact in deep roadways are proposed. 展开更多
关键词 Deep roadway Dynamic impact simulation High stress Fault slip Occurrence law
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Impact of Burial Dissolution on the Development of Ultradeep Fault-controlled Carbonate Reservoirs:Insights from High-temperature and High-pressure Dissolution Kinetic Simulation 被引量:1
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作者 TAN Xiaolin ZENG Lianbo +6 位作者 SHE Min LI Hao MAO Zhe SONG Yichen YAO Yingtao WANG Junpeng LU Yuzhen 《Acta Geologica Sinica(English Edition)》 2025年第1期228-242,共15页
Burial dissolution is a critical diagenetic process influencing ultra-deep carbonate reservoir development and preservation.Artificial carbonate samples with different internal structures were prepared,and high-temper... Burial dissolution is a critical diagenetic process influencing ultra-deep carbonate reservoir development and preservation.Artificial carbonate samples with different internal structures were prepared,and high-temperature and highpressure dissolution kinetic simulations were conducted.The results demonstrate that the intensity of burial dissolution is controlled by temperature and pressure,while tectonic-fluid activity influences the development pattern of burial dissolution,ultimately determining the direction of its differential modification.Extensive burial dissolution is likely to occur primarily at relatively shallow depths,significantly influencing reservoir formation,preservation,modification,and adjustment.The development of faults facilitates the maintenance of the intensity of burial dissolution.The maximum intensity of burial dissolution occurs at the tips and overlap zones of faults and intersections of multiple faults.The larger the scale of the faults,the more conducive it is to the development of burial dissolution.Burial dissolution fosters the formation of fault networks characterized by enhanced reservoir capacity and permeability.Burial dissolution controlled by episodic tectonic-fluid activity is a plausible explanation for forming the Tarim Basin's ultra-deep fault-controlled“stringbead-like”reservoirs. 展开更多
关键词 burial dissolution tectonic-fluid ultra-deep carbonate reservoirs high-temperature and high-pressure dissolution kinetic simulation
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Graded density impactor design via machine learning and numerical simulation:Achieve controllable stress and strain rate 被引量:1
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作者 Yahui Huang Ruizhi Zhang +6 位作者 Shuaixiong Liu Jian Peng Yong Liu Han Chen Jian Zhang Guoqiang Luo Qiang Shen 《Defence Technology(防务技术)》 2025年第9期262-273,共12页
The graded density impactor(GDI)dynamic loading technique is crucial for acquiring the dynamic physical property parameters of materials used in weapons.The accuracy and timeliness of GDI structural design are key to ... The graded density impactor(GDI)dynamic loading technique is crucial for acquiring the dynamic physical property parameters of materials used in weapons.The accuracy and timeliness of GDI structural design are key to achieving controllable stress-strain rate loading.In this study,we have,for the first time,combined one-dimensional fluid computational software with machine learning methods.We first elucidated the mechanisms by which GDI structures control stress and strain rates.Subsequently,we constructed a machine learning model to create a structure-property response surface.The results show that altering the loading velocity and interlayer thickness has a pronounced regulatory effect on stress and strain rates.In contrast,the impedance distribution index and target thickness have less significant effects on stress regulation,although there is a matching relationship between target thickness and interlayer thickness.Compared with traditional design methods,the machine learning approach offers a10^(4)—10^(5)times increase in efficiency and the potential to achieve a global optimum,holding promise for guiding the design of GDI. 展开更多
关键词 Machine learning Numerical simulation Graded density impactor Controllable stress-strain rate loading Response surface methodology
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Landscape Stability Assessment and Simulation Analysis Under Urban Expansion:A Case Study of Hangzhou,China 被引量:1
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作者 PEI Hui ZHANG Lin +4 位作者 ZHOU Minli NIE Wenbin ZHOU Shihao SHI Yan PAN Jianyun 《Chinese Geographical Science》 2025年第2期311-325,共15页
In recent years,rapid urbanization has had a profound impact on landscape stability.As a typical example of China's rapid urbanization,Hangzhou has also experienced significant landscape changes,which have profoun... In recent years,rapid urbanization has had a profound impact on landscape stability.As a typical example of China's rapid urbanization,Hangzhou has also experienced significant landscape changes,which have profoundly affected its ecological stability.Taking Hangzhou as an example,this study integrates land use change data from 1980 to 2020,combines dynamic simulation and ecological modeling techniques,and carries out a comprehensive analysis of historical trends and future predictions,to provide valuable insights into the complex interactions between urban expansion and landscape stability.The results indicate that:1)between 1980 and2020,Hangzhou experienced a significant increase in construction land at the expense of arable land,leading to a gradual decline in landscape stability,though the downward trend has slowed in recent years.2)The spatial distribution of landscape stability shows clear aggregation patterns,with lower stability concentrated in economically active flatlands and higher stability in the mountainous western regions.3)By 2040,further urban expansion is predicted to occur alongside increased landscape integration,reflecting the positive effects of ecological protection strategies.This study highlights the universal challenges of balancing economic growth with ecological stability in rapidly urbanizing regions.The combination of advanced simulation models and spatiotemporal analysis demonstrates a replicable framework for assessing urban expansion's ecological impacts.These findings underscore the importance of tailoring urban planning and ecological policies to address regional disparities,providing valuable insights for sustainable urban development and landscape management globally. 展开更多
关键词 landscape stability stability index Future Land Use simulation(FLUS)model Hangzhou China
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Numerical Simulation and Analysis of Heat Treatment Processes on AISI 1025 Steel Produced by Laser Engineered Net Shaping
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作者 Elphas Tum Rehema Ndeda +3 位作者 James Mutua Raghupatruni Prasad Eyitao Olakanmi Sisa Pityana 《Modeling and Numerical Simulation of Material Science》 2025年第1期1-15,共15页
Heat treatment processes, such as annealing and quenching, are crucial in determining residual stress evolution, microstructural changes and mechanical properties of metallic materials, with residual stresses playing ... Heat treatment processes, such as annealing and quenching, are crucial in determining residual stress evolution, microstructural changes and mechanical properties of metallic materials, with residual stresses playing a greater role in the performance of components. This paper investigates the effect of heat treatment on residual stresses induced in AISI 1025, manufactured using LENS. Finite element model was developed and simulated to analyze residual stress development. AISI 1025 samples suitable for tool and die applications in Fused Deposition Modelling (FDM) filament production, were fabricated using Laser Engineered Net Shaping (LENS) process, followed by heat treatment where annealing and quenching processes were done. The material’s microstructure, residual stress and hardness of heat-treated samples under investigation, were compared against the as-built samples. The results indicated that after annealing, tensile residual stresses were reduced by 93%, resulting in a reduced crack growth rate, compared to the as-built sample, although the hardness was reduced significantly by 25%. On the other hand, high tensile residual stresses of 425 ± 14 MPa were recorded after quenching process with an improvement of hardness by 21%. 展开更多
关键词 Heat Treatment Residual Stresses HARDNEss Microstructure Numerical simulation
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Probabilistic Site Investigation Optimization of Gassy Soils Based on Conditional Random Field and Monte Carlo Simulation
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作者 Shaolin Ding 《World Journal of Engineering and Technology》 2025年第1期1-11,共11页
Gassy soils are distributed in relatively shallow layers the Quaternary deposit in Hangzhou Bay area. The shallow gassy soils significantly affect the construction of underground projects. Proper characterization of s... Gassy soils are distributed in relatively shallow layers the Quaternary deposit in Hangzhou Bay area. The shallow gassy soils significantly affect the construction of underground projects. Proper characterization of spatial distribution of shallow gassy soils is indispensable prior to construction of underground projects in the area. Due to the costly conditions required in the site investigation for gassy soils, only a limited number of gas pressure data can be obtained in engineering practice, which leads to the uncertainty in characterizing spatial distribution of gassy soils. Determining the number of boreholes for investigating gassy soils and their corresponding locations is pivotal to reducing construction risk induced by gassy soils. However, this primarily relies on the engineering experience in the current site investigation practice. This study develops a probabilistic site investigation optimization method for planning investigation schemes (including the number and locations of boreholes) of gassy soils based on the conditional random field and Monte Carlo simulation. The proposed method aims to provide an optimal investigation scheme before the site investigation based on prior knowledge. Finally, the proposed approach is illustrated using a case study. 展开更多
关键词 Gassy Soils Site Investigation UNCERTAINTY Conditional Random Field Monte Carlo simulation
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Coarse-grained molecular dynamics simulations on self-assembly of polystyrene-block-poly(2-vinylpyridine)
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作者 Daiwen Li Shoutian Qiu +6 位作者 Gan Liu Ming Liu Mingjie Wei Shipeng Sun Weihong Xing Xiaohua Lu Yong Wang 《Chinese Journal of Chemical Engineering》 2025年第7期15-25,共11页
Self-assembly of block copolymers(BCPs)is highly intricate and is adsorbing extensive experimental and simulation efforts to reveal it for maximizing structural order and device performances.The coarse-grained(CG)mole... Self-assembly of block copolymers(BCPs)is highly intricate and is adsorbing extensive experimental and simulation efforts to reveal it for maximizing structural order and device performances.The coarse-grained(CG)molecular dynamics(MD)simulation offers a microscopic angle to view the self-assembly of BCPs.Although some molecular details are sacrificed during CG processes,this method exhibits remarkable computational efficiency.In this study,a comprehensive CG model for polystyrene-block-poly(2-vinylpyridine),PS-b-P2VP,one of the most extensively studied BCPs for its high Flory-Huggins interaction parameter,is constructed,with parameters optimized using target values derived from all-atom MD simulations.The CG model precisely coincides with various classical self-assembling morphologies observed in experimental studies,matching the theoretical phase diagrams.Moreover,the conformational asymmetry of the experimental phase diagram is also clearly revealed by our simulation results,and the phase boundaries obtained from simulations are highly consistent with experimental results.The CG model is expected to extend to simulate the self-assembly behaviors of other BCPs in addition to PS-b-P2VP,thus increasing understanding of the microphase separation of BCPs from the molecular level. 展开更多
关键词 Block copolymers SELF-AssEMBLY Martini force field POLYMERS Computer simulation Molecular simulation
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Plastic flow and interfacial bonding behaviors of embedded linear friction welding process:Numerical simulation combined with thermophysical experiment
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作者 Tiejun MA Zhenguo GUO +6 位作者 Xiawei YANG Junlong JIN Xi CHEN Jun TAO Wenya LI Achilles VAIRIS Liukuan YU 《Chinese Journal of Aeronautics》 2025年第1期87-98,共12页
In this study,a new linear friction welding(LFW)process,embedded LFW process,was put forward,which was mainly applied to combination manufacturing of long or overlong loadcarrying titanium alloy structural components ... In this study,a new linear friction welding(LFW)process,embedded LFW process,was put forward,which was mainly applied to combination manufacturing of long or overlong loadcarrying titanium alloy structural components in aircraft.The interfacial plastic flow behavior and bonding mechanism of this process were investigated by a developed coupling EulerianLagrangian numerical model using software ABAQUS and a novel thermo-physical simulation method with designed embedded hot compression specimen.In addition,the formation mechanism and control method of welding defects caused by uneven plastic flow were discussed.The results reveal that the plastic flow along oscillating direction of this process is even and sufficient.In the direction perpendicular to oscillation,thermo-plastic metals mainly flow downward along welding interface under coupling of shear stress and interfacial pressure,resulting in the interfacial plastic zone shown as an inverted“V”shape.The upward plastic flow in this direction is relatively weak,and only a small amount of flash is extruded from top of joint.Moreover,the wedge block and welding components at top of joint are always in un-steady friction stage,leading to nonuniform temperature field distribution and un-welded defects.According to the results of numerical simulation,high oscillating frequency combined with low pressure and small amplitude is considered as appropriate parameter selection scheme to improve the upward interfacial plastic flow at top of joint and suppress the un-welded defects.The results of thermo-physical simulation illustrate that continuous dynamic recrystallization(CDRX)induces the bonding of interface,accompanying by intense dislocation movement and creation of many low-angle grain boundaries.In the interfacial bonding area,grain orientation is random with relatively low texture density(5.0 mud)owing to CDRX. 展开更多
关键词 Embedded linear friction welding Plastic flow Interfacial bonding behavior Numerical simulation Thermo-physical simulation Temperature field Dynamic recrystallization
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Frequency-domain electromagnetic simulation of UXO based on HFSS-MATLAB-API
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作者 SUN Zhongqiu LIU Sixin +1 位作者 TIAN Sen LU Qi 《Global Geology》 2025年第4期251-264,共14页
The detection of unexploded ordnance(UXO)is critical for battlefield clearance and civilian safety.This study presents the development of a software for automated simulation based on the high frequency structure simul... The detection of unexploded ordnance(UXO)is critical for battlefield clearance and civilian safety.This study presents the development of a software for automated simulation based on the high frequency structure simulator(HFSS)and the MATLAB application programming interface(API),which together form the HFSS-MATLAB-API.This interface enables control over HFSS and conducts frequency-domain electromagnetic simulations for various types of UXO,including anti-tank mines,grenades,mortars,and aerial bombs.The software automates modelling,solving,data extraction,and analysis through MATLAB,enhancing the efficiency of simulation and enabling flexible settings for target models,coil parameters,and subsurface media.The research utilizes numerical simulation methods to analyze the response characteristics of different types of UXO in electromagnetic induction and explores the impact of the rotation angle of the target model on the attenuation characteristics of the measurement line.The results indicate that the electromagnetic response of UXO varies significantly based on type,burial depth,and spatial orientation.The findings provide a theoretical foundation for the electromagnetic detection,target identification,and classification of UXO. 展开更多
关键词 HFss-MATLAB-API frequency-domain electromagnetic UXO simulation
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Model Design and Simulation of an 80 kW Capacitor Coupled Substation Derived from a 132 kV Transmission Line
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作者 Sinqobile Wiseman Nene Bolanle Tolulope Abe Agha Francis Nnachi 《Open Journal of Modelling and Simulation》 2025年第1期1-19,共19页
The global rise in energy demand, particularly in remote and sparsely populated regions, necessitates innovative and cost-effective electrical distribution solutions. Traditional Rural Electrification (RE) methods, li... The global rise in energy demand, particularly in remote and sparsely populated regions, necessitates innovative and cost-effective electrical distribution solutions. Traditional Rural Electrification (RE) methods, like Conventional Rural Electrification (CRE), have proven economically unfeasible in such areas due to high infrastructure costs and low electricity demand. Consequently, Unconventional Rural Electrification (URE) technologies, such as Capacitor Coupled Substations (CCS), are gaining attention as viable alternatives. This study presents the design and simulation of an 80 kW CCS system, which taps power directly from a 132 kV transmission line to supply low-voltage consumers. The critical components of the CCS, the capacitors are calculated, then a MATLAB/Simulink model with the attained results is executed. Mathematical representation and state-space representation for maintaining the desired tapped voltage area also developed. The research further explores the feasibility and operational performance of this CCS configuration, aiming to address the challenges of rural electrification by offering a sustainable and scalable solution. The results show that the desired value of the tapped voltage can be achieved at any level of High Voltage (HV) with the selection of capacitors that are correctly rated. With an adequately designed control strategy, the research also shows that tapped voltage can be attained under both steady-state and dynamic loads. By leveraging CCS technology, the study demonstrates the potential for delivering reliable electricity to underserved areas, highlighting the system’s practicality and effectiveness in overcoming the limitations of conventional distribution methods. 展开更多
关键词 Capacitor-Coupled Substation Transmission Line-linked Capacitor-Coupled Substation Capacitor-Coupled Substation simulation MICROGRIDS Rural Electrification Power System Modeling
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Quantum-enriched large-eddy simulation with the incompressible Schrodinger flow
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作者 Zishuo Han Yue Yang 《Acta Mechanica Sinica》 2025年第1期95-105,共11页
We propose a hybrid quantum-classical method,the quantum-enriched large eddy simulation(QELES),for simulating turbulence.The QELES combines the large-scale motion of the large eddy simulation(LES)and the subgrid motio... We propose a hybrid quantum-classical method,the quantum-enriched large eddy simulation(QELES),for simulating turbulence.The QELES combines the large-scale motion of the large eddy simulation(LES)and the subgrid motion of the incompressible Schrodinger flow(ISF).The ISF is a possible way to be simulated on a quantum computer,and it generates subgrid scale turbu-lent structures to enrich the LES field.The enriched LES field can be further used in turbulent combustion and multi-phase flows in which the subgrid scale motion plays an important role.As a conceptual study,we perform the simulations of ISF and LES separately on a classical computer to simulate decaying homogeneous isotropic turbulence.Then,the QEI ES velocity is obtained by the time matching and the spectral blending methods.The QEL ES achieves significant improvement in predicting the energy spectrum,probaility density functions of velocity and vorticity components,and velocity structure functions,and reconstructs coherent small-scales vortices in the direct numerical simulation(DNS).On the other hand,the vortices in the QELES are less elongated and tangled than those in the DNS,and the magnitude of the third-order structure function in the QELES is less than that in the DNS,due to the diferent constitutive relations in the viscous flow and ISE. 展开更多
关键词 Quantum computing Large-eddy simulation Subgrid motion
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Improving the reliability of classical molecular dynamics simulations in battery electrolyte design
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作者 Xin He Yujie Zhang +5 位作者 Haomiao Li Min Zhou Wei Wang Ruxing Wang Kai Jiang Kangli Wang 《Journal of Energy Chemistry》 2025年第2期34-41,I0002,共9页
Explorations into new electrolytes have highlighted the critical impact of solvation structure on battery performance,Classical molecular dynamics(CMD)using semi-empirical force fields has become an essential tool for... Explorations into new electrolytes have highlighted the critical impact of solvation structure on battery performance,Classical molecular dynamics(CMD)using semi-empirical force fields has become an essential tool for simulating solvation structures.However,mainstream force fields often lack accuracy in describing strong ion-solvent interactions,causing disparities between CMD simulations and experimental observations.Although some empirical methods have been employed in some of the studies to address this issue,their effectiveness has been limited.Our CMD research,supported by quantum chemical calculations and experimental data,reveals that the solvation structure is influenced not only by the charge model but also by the polarization description.Previous empirical approaches that focused solely on adjusting ion-solvent interaction strengths overlooked the importance of polarization effects.Building on this insight,we propose integrating the Drude polarization model into mainstream force fields and verify its feasibility in carbonate,ether,and nitrile electrolytes.Our experimental results demonstrate that this approach significantly enhances the accuracy of CMD-simulated solvation structures.This work is expected to provide a more reliable CMD method for electrolyte design,shielding researchers from the pitfalls of erroneous simulation outcomes. 展开更多
关键词 ELECTROLYTE Classical molecular dynamics Solvation structure simulations
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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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Research on the Optimization and Simulation of Assembly Line Balancing Based on Improved PSO Algorithm
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作者 Wenkang Zhang 《Journal of World Architecture》 2025年第3期159-168,共10页
In response to the deficiencies of commonly used optimization methods for assembly lines,a production demand-oriented optimization method for assembly lines is proposed.Taking a certain compressor assembly line as an ... In response to the deficiencies of commonly used optimization methods for assembly lines,a production demand-oriented optimization method for assembly lines is proposed.Taking a certain compressor assembly line as an example,the production rhythm and the number of workstations are calculated based on production requirements and working systems.With assembly rhythm and smoothing index as optimization goals,an improved particle swarm optimization algorithm is employed for process allocation.Subsequently,Flexsim simulation is used to analyze the assembly line.The final results show that after optimization using the improved particle swarm algorithm,the assembly line balance rate increased from 71.1%to 85.9%,and the assembly line smoothing index decreased from 47.4 to 29.8,significantly enhancing assembly efficiency.This demonstrates the effectiveness of the proposed optimization method for the assembly line and provides a reference for other products in the same industry. 展开更多
关键词 Assembly line balance Improve PSO simulation optimization
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Assessment of shear wave velocity models in the Southeast Qinghai-Xizang Plateau with full-wave simulation
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作者 Wenpei Miao Guoliang Li +2 位作者 Fenglin Niu Kai Tao Yonghua Li 《Earthquake Science》 2025年第3期159-171,共13页
Various velocity models have been built for Southeast Qinghai-Xizang Plateau with the purpose of revealing the internal dynamics and estimating local seismic hazards.In this study,we use a 3-D full-waveform modeling p... Various velocity models have been built for Southeast Qinghai-Xizang Plateau with the purpose of revealing the internal dynamics and estimating local seismic hazards.In this study,we use a 3-D full-waveform modeling package to systematically validate three published continental-scale velocity models,that is,Shen2016,FWEA18,and USTClitho1.0,leveraging the ample datasets in Southeast Qinghai-Xizang Plateau region.Travel time residuals and waveform similarities are measured between observed empirical Green’s functions and synthetic waveforms.The results show that the Shen2016 model,derived from traditional surface wave tomography,performs best in fitting Rayleigh waves in the Southeast Qinghai-Xizang Plateau,followed by FWEA18,built from full-waveform inversion of long-period body and surface waves.The USTClitho1.0 model,although inverted from body wave datasets,is comparable with FWEA18 in fitting Rayleigh waves.The results also show that all the models are faster than the ground-truth model and show relatively large travel-time residuals and poor waveform similarities at shorter period bands,possibly caused by small-scale structural heterogeneities in the shallower crust.We further invert the time residuals for spatial velocity residuals and reveal that all three models underestimate the amplitudes of high-and low-velocity anomalies.The underestimated amplitude is up to 4%,which is non-negligible considering that the overall amplitude of anomalies is only 5%−10%in the crust.These results suggest that datasets and the inversion method are both essential to building accurate models and further refinements of these models are necessary. 展开更多
关键词 Qinghai-Xizang Plateau tomography models fullwave simulation model validation
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Numerical simulation of 3D supersonic asymmetric truncated nozzle based on k-kL algebraic stress model
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作者 Gang WANG Shuai ZHANG +1 位作者 Jifa ZHANG Yao ZHENG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第3期238-251,共14页
The nozzle is a critical component responsible for generating most of the net thrust in a scramjet engine.The quality of its design directly affects the performance of the entire propulsion system.However,most turbule... The nozzle is a critical component responsible for generating most of the net thrust in a scramjet engine.The quality of its design directly affects the performance of the entire propulsion system.However,most turbulence models struggle to make accurate predictions for subsonic and supersonic flows in nozzles.In this study,we explored a novel model,the algebraic stress model k-kL-ARSM+J,to enhance the accuracy of turbulence numerical simulations.This new model was used to conduct numerical simulations of the design and off-design performance of a 3D supersonic asymmetric truncated nozzle designed in our laboratory,with the aim of providing a realistic pattern of changes.The research indicates that,compared to linear eddy viscosity turbulence models such as k-kL and shear stress transport(SST),the k-kL-ARSM+J algebraic stress model shows better accuracy in predicting the performance of supersonic nozzles.Its predictions were identical to the experimental values,enabling precise calculations of the nozzle.The performance trends of the nozzle are as follows:as the inlet Mach number increases,both thrust and pitching moment increase,but the rate of increase slows down.Lift peaks near the design Mach number and then rapidly decreases.With increasing inlet pressure,the nozzle thrust,lift,and pitching moment all show linear growth.As the flight altitude rises,the internal flow field within the nozzle remains relatively consistent due to the same supersonic nozzle inlet flow conditions.However,external to the nozzle,the change in external flow pressure results in the nozzle exit transitioning from over-expanded to under-expanded,leading to a shear layer behind the nozzle that initially converges towards the nozzle center and then diverges. 展开更多
关键词 Supersonic nozzle Turbulence model Numerical simulation Performance analysis
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Simulation study on the influence of the peeling material position on the discharge process of a Hall thruster
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作者 Yizhou JIN Siyuan DONG +2 位作者 Bo YU Yan ZHANG Peng MIAO 《Plasma Science and Technology》 2025年第6期69-77,共9页
The deposition layer on the discharge channel wall of a Hall thruster after long-term operation occasionally detaches from the wall and interferes with the plasma inside the channel,resulting in current pulse and thre... The deposition layer on the discharge channel wall of a Hall thruster after long-term operation occasionally detaches from the wall and interferes with the plasma inside the channel,resulting in current pulse and threatening the power supply.To understand the generation mechanism of the current pulse,the interaction between the peeling material and the channel plasma was studied by the particle-in-cell and Monte Carlo collision(PIC/MCC)method.The plasma evolution and distribution in the Hall thruster channel when peeling material existed were simulated.Simulation results show that the peeling material changes the electron transportation and ionization,and the effects are related to the position of the peeling material.When the peeling material invades the zone where the ionization rate is originally the highest without peeling material,the ionization process is almost terminated.The ionization suppression by the peeling material will cause the propellant gas to refill the channel exit.As the peeling material moves away,gas discharge is induced near the channel exit,resulting in anode current pulse. 展开更多
关键词 Hall thruster peeling material discharge disturbance PIC simulation
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An Integrated System Evaluation Engine for Cross-Domain Simulation and Design Optimization of a Transceiver Front-End Dealing with Complex OFDM Signals
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作者 Hu Chunyu Shi Weimin +1 位作者 Li Mingyu C.Patrick Yue 《China Communications》 2025年第12期183-193,共11页
Traditionally,a continuous-wave(CW)signal is used to simulate RF circuits during the design procedure,while the fabricated circuits are measured by modulated signals in the test phase,because modulated signals are use... Traditionally,a continuous-wave(CW)signal is used to simulate RF circuits during the design procedure,while the fabricated circuits are measured by modulated signals in the test phase,because modulated signals are used in reality.It is almost impossible to use a CW signal to predict system performances,such as error vector magnitude(EVM),bit error rate(BER),etc.,of a transceiver front-end when dealing with complex modulated signals.This paper develops an integrated system evaluation engine(ISEE)to evaluate the system performances of a transceiver front-end or its sub-circuits.This crossdomain simulation platform is based on Matlab,advanced design system(ADS),and Cadence simulators to link the baseband signals and transceiver frond-end.An orthogonal frequency division multiplex(OFDM)modem is implemented in Matlab for evaluating the system performances.The modulated baseband signal from Matlab is dynamically fed into ADS,which includes transceiver front-end for co-simulation.The sub-block circuits of the transceiver front-end can be implemented using ADS and Cadence simulators.After system-level circuit simulation in ADS,the output signal is dynamically delivered to Matlab for demodulation.To simplify the use of the co-simulation platform,a graphical user interface(GUI)is constructed using Matlab.The parameters of the OFDM signals can be easily reconfigured on the GUI to simulate RF circuits with different modulation schemes.To demonstrate the effectiveness of the ISEE,a 3.5 GHz power amplifier is simulated and characterized using 20 MHz 16-and 64-QAM OFDM signals. 展开更多
关键词 cross-domain simulation OFDM signal power amplifier transceiver front-end
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Numerical Simulation on Heat Dissipation Characteristics of Electronic Components with Different Heat Sink Arrangements in High-Performance Server
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作者 Zerui Chen Xin Wu +2 位作者 Houpeng Hu Yang Zhou Shang Yang 《Frontiers in Heat and Mass Transfer》 2025年第3期991-1011,共21页
As the integration of electronic components in high-performance servers increases,heat generation significantly impacts performance and raises failure rates.Therefore,heat dissipation has become a critical concern in ... As the integration of electronic components in high-performance servers increases,heat generation significantly impacts performance and raises failure rates.Therefore,heat dissipation has become a critical concern in electronic circuit design.This study uses numerical simulations to investigate the heat dissipation characteristics of electronic components in air-cooled servers.By adjusting airflow speed,heat sink configurations,and the arrangement of straight-fin heat sinks,we optimize heat dissipation performance and analyze the mechanisms at different airflow speeds.The results show that,at the same airflow speed,the temperature of the heat sink is lower than that of the electronic components,creating a temperature gradient that enhances heat transfer.Compared to a front-to-back arrangement of two straight-fin heat sinks,placing the heat sinks parallel to each other results in a lower maximum component temperature and better temperature uniformity.Heat sinks with fins significantly improve heat dissipation.The heat sink with semicylindrical fins on the rib surface provides the best cooling performance.Moreover,compared to natural convection,the maximum temperature of the electronic components decreases by 56.17%and 61%when the incoming flow velocity is 6 m/s with two parallel flat ribbed heat sinks and front-to-back arrangement,respectively. 展开更多
关键词 Electronic components numerical simulation heat dissipation structure optimization
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