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水道港口 2010年第5期31卷 321-321页

作者： Hang Tuah. Salim Faculty of Civil Engineering and Environment Institute Technology Bandung

Belawan is the largest port serving North Sumatra for the import and *** has facilities for handling container,CPO liquid bulk cargo,Oil,and other agriculture *** location is at the river mouth which is subjected to the heavy sedimentation especially after many deforestation activities in its catchment area. The numerical modeling was developed for predicting the rate of sediment caused by erosion in the catchment area for several *** predicted rate of sediment was applied as input to model of sedimentation in the *** condition of sedimentation data was used as calibrated *** integrated model was used to simulate the sedimentation in Belawan access channel and harbor basin for several development plans.

关键词： numerical model sedimentation Belawan Port

Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation

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China Foundry 2024年第1期21卷 29-43页

作者： Zhao-yang Yin Qi-chi Le Yan-chao Jiang Da-zhi Zhao Qi-yu Liao Qi Zou Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy *** effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in ***,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct *** a result,various acoustic pressure distributions and cavitation regions are *** spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical *** the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution *** acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20).

关键词： dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy

A numerical Gas Fracturing model of Coupled Thermal,Flowing and Mechanical Effects

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Computers, Materials & Continua 2020年第12期65卷 2123-2141页

作者： Dan Ma Hongyu Duan Qi Zhang Jixiong Zhang Wenxuan Li Zilong Zhou Weitao Liu State Key Laboratory of Coal Resources and Safe Mining School of MinesChina University of Mining&TechnologyXuzhou221116China School of Resources&Safety Engineering Central South UniversityChangsha410083China Beijing Research Institute of Uranium Geology Beijing100029China State Key Laboratory of Mining Disaster Prevention and Control Shandong University of Science and TechnologyQingdao266590China

Gas fracturing,which overcomes the limitation of hydraulic fracturing,is a potential alternative technology for the development of unconventional gas and oil ***,the mechanical principle of gas fracturing has not been learned comprehensively when the fluid is injected into the *** this paper,a damage-based model of coupled thermal-flowing-mechanical effects was adopted to illustrate the mechanical principle of gas *** simulation tools Comsol Multiphysics and Matlab were integrated to simulate the coupled process during the gas ***,the damage evolution of drilling areas under several conditions was fully *** results indicate that the maximum tensile stress,which occurs in the upper and lower of the injection hole,decreases with the increase of the tectonic stress coefficient(TSC).As the TSC increases,shear fractures increase,a crushed area is gradually formed and the seepage area increases *** influence of TSC on fracture expansion is concluded as follows:with the decrease of TSC,the relative width of fractures decreases whilst the depth *** indicates that thermal stress and pore pressure promote the expansion of tensile fractures but restrain the expansion of shear ***,a relatively lower injection gas pressure is required to obtain the same degree of fracturing with a coupled thermal gradient.

关键词： Gas fracturing thermal-flowing-mechanical model damage evolution numerical model

Hydrodynamic Assessment of A New Nature-Based Armour Unit on Rubble Mound Breakwater for Coastal Protection

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China Ocean Engineering 2024年第3期38卷 439-452页

作者： Ehsan SAFA Alireza MOJTAHEDI Abdolmajid MOHAMMADIAN Mohamad Ali Lotfollahi YAGHIN Department of Water Resources Engineering Faculty of Civil EngineeringUniversity of TabrizTabriz ***Iran Faculty of Civil Engineering University of OttawaOttawa K1H 8M5Canada

This research proposes a novel nature-based design of a new concrete armour unit for the cover layer of a rubblemoundbreakwater. Armour units are versatile with respect to shape, orientation, surface condition details, and ***, a detailed analysis is required to investigate the exact state of their hydraulic interactions and structuralresponses. In this regard, the performance results of several traditional armour units, including the Antifer cube,Tetrapod, X-block and natural stone, are considered for the first step of this study. Then, the related observed resultsare compared with those obtained for a newly designed (artificial coral) armour unit. The research methodology utilizesthe common wave flume test procedure. Furthermore, several verified numerical models in OpenFOAM code areused to gain the extra required data. The proposed armour is configured to provide an effective shore protection as anenvironmental-friendly coastal structure. Thus it is designed with a main trunk including deep grooves to imitate thetypical geometry of a coral type configuration, so as to attain desirable performance. The observed results and ananalytic hierarchy process (AHP) concept are used to compare the hydraulic performance of the studied traditionaland newly proposed (artificial coral) armour units. The results indicate that the artificial coral armour unit demonstratesacceptable performance. The widely used traditional armour units might be replaced by newer designs for betterwave energy dissipation, and more importantly, for fewer adverse effects on the marine environment.

关键词： rubble mound breakwater hydraulic interaction armour unit analytic hierarchy process numerical model

Experimental and numerical study on ignition and combustion characteristics of boron-magnesium composite powders

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Particuology 2024年第1期84卷 12-29页

作者： Shuyuan Liu Luyang Han Hongmei Liu Yingkai Song Linlin Liu Songqi Hu Science and Technology on Combustion Internal Flow and Thermo-Structure LaboratoryNorthwestern Polytechnical UniversityXi'an710072China School of Mechanical Engineering and Rail Transit Changzhou UniversityChangzhou213164China Shanghai Institute of Space Propulsion Shanghai201112China Shanghai Engineering Research Center of Space Engine Shanghai201112China

A high-pressure laser ignition and combustion system with adjustable oxidizer gas atmosphere is established to investigate the ignition and combustion characteristics of boron-magnesium(BM)com-posite *** ignition and combustion model of BM powders is established and validated in the present *** results show that increasing water content,O_(2) content and Mg content all result in shorter ignition delay time of BM powders,among which the effect of water content is the most ***,ignition delay time increases as pressure *** combustion time decreases with increasing Mg content and ambient pressure but increases with water *** the increase of O_(2) content,combustion time of BM powders first increases and then decreases,which means a critical O_(2) content exists above which combustion time *** results show that there exists a trade-off between ignition and combustion performance of BM composite powders.

关键词： Boron magnesium powder Laser ignition Ignition and combustion model Reaction mechanism numerical model

Experimental and numerical investigation on alternatives to sandy gravel

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Defence Technology（防务技术） 2024年第1期31卷 130-141页

作者： V.Denefeld H.Aurich Fraunhofer Institute for High-Speed Dynamics Ernst-Mach-Institut(EMI)Ernst-Zermelo-Str.479104FreiburgGermany Fraunhofer Institute for High-Speed Dynamics Ernst-Mach-Institut(EMI)Am Christianswuhr 279400KandernGermany

The NATO agreement STANAG 4569 defines the protection levels for the occupants of logistic and light armored *** Allied Engineering Publication,AEP-55,Volume 2 document outlines the test conditions for underbelly improvised explosive device(IEDs),which must be buried in water-saturated sandy *** use of sandy gravel has some drawbacks,for instance reproducibility,time consumption,and *** paper focuses on the investigation of four alternatives to sandy gravel,which could produce similar specific and cumulative impulses:a concrete pot filled with water,a concrete pot filled with quartz sand,a steel pot without filling and a concrete pot filled with glass spheres(diameter 200μm—300μm)and different water *** impulses are measured with a ring technology developed at the Fraunhofer EMI.A numerical soil model based on the work of Marrs,2014 and Fi serov a,2006 and considering the soil moisture was used to simulate the experiments with glass spheres at different water contents,showing much better agreement with the experiments than the classical Laine&Sandvik model,even for high saturation *** results can be used to create new test conditions at original scale that are more cost-effective,more reproducible and simpler to manage in comparison to the current tests carried out with STANAG sandy gravel.

关键词： Improvised explosive device(IED) Specific impulse Momentum transfer Sandy gravel Glass spheres numerical model Soil moisture

A comprehensive review of the modeling of transport phenomenon in the flow channels of polymer electrolyte membrane fuel cells

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Frontiers of Chemical Science and Engineering 2024年第8期18卷 123-161页

作者： Niyi Olukayode Shenrong Ye Mingruo Hu Yanjun Dai Rui Chen Sheng Sui Institute of Fuel Cell Shanghai Jiao Tong UniversityShanghai 200240China Institute of Refrigeration and Cryogenics Shanghai Jiao Tong UniversityShanghai 200240China Low Carbon Engineering Loughborough UniversityLoughborough Leicestershire LE113TUUK

Reactant gas and liquid water transport phenomena in the flow channels are complex and critical to the performance and durability of polymer electrolyte membrane fuel *** polymer membrane needs water at an optimum level for proton *** management involves the prevention of dehydration,waterlogging,and the cell’s subsequent performance decline and *** process requires the study and understanding of internal two-phase *** experimental visualization techniques are used to study two-phase flows in polymer electrolyte membrane fuel ***,the experiments have limitations in in situ measurements;they are also expensive and time *** contrast,numerical modeling is cheaper and faster,providing insights into the complex multiscale processes occurring across the components of the polymer electrolyte membrane fuel *** paper introduces the recent design of flow *** reviews the numerical modeling techniques adopted for the transport phenomena therein:the two-fluid,multiphase mixture,volume of fluid,lattice Boltzmann,and pressure drop ***,this work describes,compares,and analyses the models’approaches and reviews the representative results of some selected ***,the paper summarizes the modeling perspectives,emphasizing future directions with some recommendations.

关键词： two-phase flows numerical model flow channel polymer electrolyte membrane fuel cells water management

Verification of A numerical Harbour Wave model

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China Ocean Engineering 2007年第4期21卷 647-658页

作者：潘军宁洪广文左其华王登婷 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute

A numerical model for wave propagation in a harbour is verified by use of physical models. The extended time-dependent mild slope equation is employed as the governing equation, and the model is solved by use of ADI method containing the relaxation factor. Firstly, the reflection coefficient of waves in front of rubble-mound breakwaters under oblique incident waves is determined through physical model tests, and it is regarded as the basis for simulating partial reflection boundaries of the numerical model. Then model tests on refraction, diffraction and reflection of waves in a harbour are performed to measure wave height distribution. Comparative results between physical and numerical model tests show that the present numerical model can satisfactorily simulate the propagation of regular and irregular waves in a harbour with complex topography and boundary conditions.

关键词： wave mild slope equation numerical model harbour verification

numerical analysis of geosynthetic-reinforced embankment performance under moving loads

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 682-696页

作者： Xuanming Ding Jinqiao Zhao Qiang Ou Jianfei Liu College of Civil Engineering Chongqing UniversityChongqing400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing400045China China United Engineering Corporation Limited Hangzhou310052China

The performance of geosynthetic-reinforced embankments under traffic moving loads is always a hotspot in the geotechnical engineering field.A three-dimensional(3D)model of a geosynthetic-reinforced embankment without drainage consolidation was established using the finite element software *** this model,the traffic loads were simulated by two moving loads of rectangular pattern,and their amplitude,range,and moving speed were realized by a Fortran *** embankment fill was simulated by an equivalent linear viscoelastic model,which can reflect its *** geogrid was simulated by the truss element,and the geocell was simulated by the membrane *** elements were utilized to weaken the boundary effect caused by the model geometry at the *** of the established numerical model was conducted by comparing the predicted deformations in the cross-section of the geosynthetic-reinforced embankment with those from the existing *** this basis,the dynamic stress and strain distribution in the pavement structure layer of the geosynthetic-reinforced embankment under a moving load was also ***,a parametric study was conducted to examine the influences of the different types of reinforcement,overload,and the moving load velocity on the geosynthetic-reinforced embankment.

关键词： Geosynthetic-reinforced layer numerical model Moving load Embankment Deformation Stress