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Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 102-110页

作者： Qiang Liu Xiang Li shen Du ming Gao Yanbin Yin Jiongming zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity

THREE-DIMENSIONAL SIMULATION OF MEANDERING RIVER BASED ON 3-D RNG k-ε TURBULENCE MODEL

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Journal of Hydrodynamics 2008年第4期20卷 448-455页

作者： zhang ming-liang shen yong-ming State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024China Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong China

A 3-D numerical model for calculating flow in non-curvilinear coordinates was established in this article. The flow was simulated by solving the full Reynolds-averaged Navier-Stokes equations with the RNG κ-ε turbulence model. In the horizontal x-y-plane, a boundary-fitted curvilinear co-ordinate system was adopted, while in the vertical direction, a σ co-ordinate transformation was used to represent the free surface and bed topography. The water level was determined by solving the 2-D Poisson equation derived from 2-D depth averaged momentum equations. The finite-volume method was used to discretize the equations and the SIMPLEC algorithm was applied to acquire the coupling of velocity and pressure. This model was applied to simulate the meandering channels and natural rivers, and the water levels and the velocities for all sections were given. By contrasting and analyzing, the agreement with measurements is generally good. The feasibility studies of simulating flow of the natural fiver have been conducted to demonstrate its applicability to hydraulic engineering research.

关键词： non-orthogonal curvilinear coordinates RNG κ-ε turbulence model 2-D Poisson equation SIMPLEC algorithm depth averaged equation

Mechanical and electronic properties of diamondlike BC_5

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第3期12卷 177-182页

作者： Qing zhang Shi-ming WANG yong-cheng liang Xinzhou Teachers University Xinzhou 034000 Shanxi China College of Engineering Science and Technology Shanghai Ocean University Shanghai 201306 China State Key Laboratory of High Performance Ceramics and Superfine Microstructures Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

The structural properties,mechanical behavior,and electronic structure of the newly developed diamondlike BC5 (d-BC5) was investigated using density functional theory (DFT) *** results indicate that d-BC5 has great bulk modulus of 393 GPa,large shear modulus of 398 GPa,and high hardness of 62 Pa,and thus support the fact that d-BC5 is an ultra-incompressible and superhard ***,the superhard d-BC5 exhibits metallic ***,the trend that the mechanical behavior falls with the increase of boron content was *** combination of huge stiffness,high hardness,and good metallicity makes series of diamondlike BCx (d-BCx) valid for wider applications in comparison with pure diamond.

关键词： Mechanical properties Metallicity Diamondlike BC5

Material removal mechanisms and characteristics of potassium dihydrogen phosphate crystals under nanoscratching

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Advances in Manufacturing 2021年第4期9卷 558-567页

作者： Ning Hou yong zhang liang-Chi zhang ming-Hai Wang School of Mechatronics Engineering Shenyang Aerospace UniversityShenyang 110136People’s Republic of China Key Laboratory of Fundamental Science for National Defense of Aeronautical Digital Manufacturing Process Shenyang Aerospace UniversityShenyang 110136People’s Republic of China School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen 518055GuangdongPeople’s Republic of China

Potassium dihydrogen phosphate(KDP)crystals are important materials in high-energy laser ***,because these crystals are brittle and soft,machining-induced defects often emerge in KDP *** study aimed to investigate the material removal mechanisms and characteristics of KDP during nanoscratching using Berkovich,spherical,and conical *** found that KDP surface layers could be removed in a ductile mode at the micro/nanoscale and that dislocation motion was one of the main removal *** characteristics are related to the stress fields generated by indenter *** spherical indenter achieved a ductile removal mode more *** lateral force of nanoscratching increased with an increase in the normal *** coefficient of friction(COF)followed the same trend as the lateral force when spherical and conical indenters were ***,the COF was independent of the normal force when using a Berkovich *** found that these COF variations could be accurately described by friction models.

关键词： Potassium dihydrogen phosphate(KDP)crystals Removal mechanism Nanoscratching Indenter geometry

Numerical simulation of stratified turbulent two-phase flow in aquatic environment

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Journal of Environmental Sciences 2000年第2期12卷 24-28页

作者： shen, yong-ming Wang, Ya-Ling liang, Chuan State Key Lab. Coast. Offshore Eng. Dalian University of Technology Dalian 116023 China State Key Hydr. Lab. High Speed F. Sichuan University Chengdu 610065 China

The two fluid model of stratified turbulent two phase flow in aquatic environment is developed in this paper. The motion of each phase is described by a unified multi fluid model in an Eulerian coordinate system. The laws of turbulent transportation for each phase, and the restriction of each other between the two phases are completely simulated. The complex two phase turbulence with strong buoyancy effects is selected to examine numerically. The extensive experimental data obtained in stratified flow are used here. Comparison of the results of numerical simulation with the experimental data is conducted. It has shown that the results of numerical simulation are satisfactory.

关键词： stratified flow two phase turbulence two fluid model aquatic environment CLC number: X131 2 Document code: A

Analytical study on water hammer pressure in pressurized conduits with a throttled surge chamber for slow closure

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Water Science and Engineering 2010年第2期3卷 174-189页

作者： yong-liang zhang ming-fei MIAO Ji-ming MA State Key Laboratory of Hydroscience and Hydraulic Engineering Department of Hydraulic Engineering Tsinghua University Beijing 100084 P. R. China

This paper presents an analytical investigation of water hammer in a hydraulic pressurized pipe system with a throttled surge chamber located at the junction between a tunnel and a penstock, and a valve positioned at the downstream end of the penstock. Analytical formulas of maximum water hammer pressures at the downstream end of the tunnel and the valve were derived for a system subjected to linear and slow valve closure. The analytical results were then compared with numerical ones obtained using the method of characteristics. There is agreement between them. The formulas can be applied to estimating water hammer pressure at the valve and transmission of water hammer pressure through the surge chamber at the junction for a hydraulic pipe system with a surge chamber.

关键词： throttled surge chamber water hammer orifice analytical formula

Modeling impact of culture facilities on hydrodynamics and solute transport in marine aquaculture waters of North Yellow Sea

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Water Science and Engineering 2023年第1期16卷 26-35页

作者： Heng-zhi Jiang yong-peng Ji ming-liang zhang National Marine Environmental Monitoring Center Dalian 116023China Beijing Jiutian Weather Co. LtdBeijing 100081China School of Ocean Science and Environment Dalian Ocean UniversityDalian 116023China

An increasing number of marine aquaculture facilities have been placed in shallow bays and open sea,which might significantly affect hydrodynamic and solute transport processes in marine aquaculture *** this study,a coupled hydrodynamic and solute transport model was developed with high-resolution schemes in marine aquaculture waters based on depth-averaged shallow water equations.A new expression of drag force was incorporated into the momentum equations to express the resistance of suspended culture *** coupled model was used to simulate the effect of suspended structures on tidal currents and the movement of a contaminant cloud in the marine aquaculture of the North Yellow Sea,*** simulation results showed a low-velocity area appearing inside the aquaculture cage area,with a maximum reduction rate of velocity close to 45%under high-density *** results also showed that tidal currents were sensitive to the density of suspended cages,the length of cages,and the drag coefficients of *** transport processes of pollutants inside aquaculture facilities were inhibited away from the vicinity of the culture cage area because of the diminished tidal ***,the suspended cages significantly affected the transport processes of pollutants in the coastal aquaculture ***,the reduced horizontal velocity significantly decreased the food supply for the aquaculture areas from the surrounding sea.

关键词： Marine aquaculture Suspended cages Numerical simulation Current reduction Solute transport

Complete kinetic model for esterification reaction of lauric acid with glycerol to synthesize glycerol monolaurate

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Chinese Journal of Chemical Engineering 2024年第6期70卷 211-221页

作者： Han-Qiao Hu Yue zhang ming Fan yong Cai Guang-Wen Chu liang-liang zhang Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Petrochemical Research Institute China National Petroleum CorporationBeijing 102206China

Glycerol monolaurate(GML)is a widely used industrial chemical with excellent emulsification and antibacterial *** direct esterification of glycerol with lauric acid is the main method to synthesize *** this work,the kinetic process of direct esterification was systematically studied using p-toluenesulfonic acid as catalyst.A complete kinetic model of consecutive esterification reaction has been established,and the kinetic equation of acid catalysis was *** isomerization reactions of GML and glycerol dilaurate were *** was found that the reaction was an equilibrium reaction and the reaction rate was faster than the esterification *** kinetic equations of the consecutive esterification reaction were obtained by experiments as k_(1)=(276+92261Xcat)exp(-37720/RT)and k_(2)=(80+4413Xcat)exp(-32240/RT).The kinetic results are beneficial to the optimization of operating conditions and reactor design in GML production process.

关键词： Glycerol monolaurate p-Toluenesulfonic acid Esterification Kinetics Mass transfer

DEVELOPMENT AND APPLICATION OF A EUTROPHICATION WATER QUALITY MODEL FOR RIVER NETWORKS

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Journal of Hydrodynamics 2008年第6期20卷 719-726页

作者： zhang ming-liang shen yong-ming GUO Yakun State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116023 China Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong China Department of Engineering University of Aberdeen Aberdeen AB24 3UE UK

The Preissmann implicit scheme was used to discretize the one-dimensional Saint-Venant equations, the river-junction-fiver method was applied to resolve the hydrodynamic and water quality model for river networks, and the key issues on the model were expatiated particularly in this article. This water quality module was designed to compute time dependent concentrations of a series of constituents, which are primarily governed by the processes of advection, dispersion and chemical reactions. Based on the theory of Water Quality Analysis Simulation Program （WASP） water quality model, emphasis was given to the simulation of the biogeochemical transformations that determine the fate of nutrients, in particular, the simulation of the aquatic cycles of nitrogen and phosphorus compounds. This model also includes procedures for the determination of growth and death of phytoplankton. This hydrodynamic and water quality model was applied to calculate two river networks. As illustrated by the numerical examples, the calculated water level and discharge agree with the measured data and the simulated trends and magnitudes of water quality constituents are generally in good agreement with field observations. It is concluded that the presented model is useful in the pollutant control and in the determination of pollutant-related problems for river networks.

关键词： Preissmann implicit scheme river networks hydrodynamic model water quality model biogeochemical transformations three-step method