检索结果-南通市图书馆

gas flow characteristics of argon inductively coupled plasma and advections of plasma species under incompressible and compressible flows

引用

Chinese Physics B 2018年第12期27卷 348-360页

作者： Shu-Xia Zhao Zhao Feng Physics Department Dalian University of Technology

In this work, incompressible and compressible flows of background gas are characterized in argon inductively coupled plasma by using a fluid model, and the respective influence of the two flows on the plasma properties is specified. In the incompressible flow, only the velocity variable is calculated, while in the compressible flow, both the velocity and density variables are calculated. The compressible flow is more realistic; nevertheless, a comparison of the two types of flow is convenient for people to investigate the respective role of velocity and density variables. The peripheral symmetric profile of metastable density near the chamber sidewall is broken in the incompressible flow. At the compressible flow, the electron density increases and the electron temperature decreases. Meanwhile, the metastable density peak shifts to the dielectric window from the discharge center, besides for the peripheral density profile distortion, similar to the incompressible *** velocity profile at incompressible flow is not altered when changing the inlet velocity, whereas clear peak shift of velocity profile from the inlet to the outlet at compressible flow is observed as increasing the gas flow rate. The shift of velocity peak is more obvious at low pressures for it is easy to compress the rarefied gas. The velocity profile variations at compressible flow show people the concrete residing processes of background molecule and plasma species in the chamber at different flow rates. Of more significance is it implied that in the usual linear method that people use to calculate the residence time, one important parameter in the gas flow dynamics, needs to be rectified. The spatial profile of pressure simulated exhibits obvious spatial gradient. This is helpful for experimentalists to understand their gas pressure measurements that are always taken at the chamber outlet. At the end, the work specification and limitations are listed.

关键词： gas flow inductively coupled plasma compressible flow fluid model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

gas flow Distribution in Pelletizing Shaft Furnace

引用

Journal of Iron and Steel Research International 2006年第6期13卷 16-20页

作者： CAI Jiu-ju DONG Hui WANG Guo-sheng YANG Jun SEPA Key Laboratory on Eco-Industry Northeastern University Shenyang 110004 Liaoning China Department ofChemical Engineering shenyang Institute of Chemical Technology Shenyang 110141 Liaoning China

Through thermal test, cold state experiment, analysis and simulation of thermal process, the gas flow distribution in pelletizing shaft furnace （PSF） was discussed. The results show that there are five flowing trends among them, the downward roasting gas and the upward cooling gas are the most unsteady, which influence flow distribution greatly. Among the operating parameters, the ratio of inflow is a key factor affecting the flow distribution. The roasting and cooling gases will entirely flow into the roasting zone and internal vertical air channels （IVAC）, respectively, if the ratio of inflow is critical. From such a critical operating condition increasing roasting gas flow or decreasing cooling gas flow, the roasting gas starts flowing downwards so as to enter the inside of IVAC the greater the ratio of inflow, the larger the downward flowrate. Among constructional parameters, the width of roasting zone b1, width of IVAC b2 and width of cooling zone b3, and the height of roasting zone h1, height of soaking zone h2 and height of cooling zone hs are the main factors affecting flow distribution. In case the ratio of b2/b3, or h3/h2, or h1/h2 is increased, the upward cooling gas tends to decrease while the downward roasting gas tends to increase with a gradual decrease in the ratio of inflow.

关键词： pellet shaft furnace fixed bed packed bed gas flow

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A numerical study on dispersion of particles from the surface of a circular cylinder placed in a gas flow using discrete vortex method

引用

Journal of Hydrodynamics 2014年第3期26卷 384-393页

作者：黄远东何文荣吴文权 KIM Chang-Nyung School of Environment and Architecture University of Shanghai for Science and Technology College of Engineering Kyung Hee University College of Engineering Kyung Hee University Yongin 449-701 Korea Industrial Liaison Research Institute Kyung Hee University

The dispersion of particles emitted from the surface of a circular cylinder placed in a gas flow at the Reynolds number of 200 000 is numerically investigated using the discrete vortex method coupled with a Lagrangian approach for solid particle tracking. The wake vortex patterns, the temporal-spatial distributions and trajectories as well as the dispersion functions for particles with various Stokes numbers（St） ranging from 0.001 to 1.0 are obtained. The numerical results reveal that：（1） Solid particles on the cylinder surface are picked up and then transported away from the cylinder by the wake vortex flow.（2） Solid particles emitted from the cylinder surface always follow the vortices in the cylinder wake, and the response of particles to wake vortices is directly related to their Stokes numbers（particles with St= 0.001, 0.0038, 0.01 can distribute both in the vortex core and around the vortex periphery, whereas those with St= 0.1, 1.0 can not enter the vortex core and congregate mainly around the vortex periphery）.（3） The particles move in rolling state in the wake region, and the dispersion intensity of particles in the lateral direction decreases remarkably as the Stokes number of particles is increased from 0.001 to 1.0.

关键词： particle dispersion circular cylinder gas flow wake vortex discrete vortex method(DVM)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Permeability evolution and gas flow in wet coal under non-equilibrium state:Considering both water swelling and process-based gas swelling

引用

International Journal of Mining Science and Technology 2023年第5期33卷 585-599页

作者： Zhiyong Xiao Gang Wang Changsheng Wang Yujing Jiang Feng Jiang Chengcheng Zheng Shandong Provincial Key Laboratory of Civil Engineering Disaster Prevention and Mitigation Shandong University of Science and TechnologyQingdao 266590China College of Civil Engineering Fujian University of TechnologyFuzhou 350118China c State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China

Accurate knowledge of gas flow within the reservoir and related controlling factors will be important for enhancing the production of coal bed *** present,most studies focused on the permeability evolution of dry coal under gas adsorption equilibrium,gas flow and gas diffusion within wet coal under the generally non-equilibrium state are often ignored in the process of gas *** this study,an improved apparent permeability model is proposed which accommodates the water and gas adsorption,stress dependence,water film thickness and gas flow *** the process of modeling,the water adsorption is only affected by water content while the gas adsorption is time and water content dependent;based on poroelastic mechanics,the effective fracture aperture and effective pore radius are derived;and then the variation in water film thickness for different pore types under the effect of water content,stress and adsorption swelling are modeled;the flow regimes are considered based on Beskok’s ***,after validation with experimental data,the proposed model was applied to numerical simulations to investigate the evolution of permeability-related factors under the effect of different water *** gas flow in wet coal under the non-equilibrium state is explicitly revealed.

关键词： gas flow Apparent permeability Water film Adsorption Non-equilibrium state

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of gas flow on the nanoparticles transport in dusty acetylene plasmas

引用

Plasma Science and Technology 2023年第10期25卷 68-74页

作者：刘相梅刘文静张茜董晓天赵书霞 School of Science Qiqihar UniversityQiqihar 161006People's Republic of China School of Physics Dalian University of TechnologyDalian 116024People's Republic of China

This article presents simulation results on the effects of neutral gas flow for nanoparticle transport in atmospheric-pressure,radio-frequency,capacitively-coupled,and acetylene *** acetylene gas is set to flow into the chamber from the upper showerhead *** internal energy of the gas medium therein is transferred into kinetic energy so the gas advection can be *** is represented by the pressure volume work term of the gas energy converse *** gas advection leads to the gas temperature sink at the gas inlet,hence a large gas temperature gradient is *** thermophoresis relies on the gas temperature gradient,and causes the profile of nanoparticle density to vary from a double-peak structure to a single-peak *** gas advection influences the properties of electron density and temperature as well and causes the drift-ambipolar mode profile of electron density *** the bulk region,*** from the inlet,the gas advection is more like one isovolumetric compression,which slightly increases the temperature of the gas medium at consuming its kinetic energy.

关键词： gas flow dusty acetylene plasmas nanoparticles transport

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

“Redistribution” Effect of Lumpy Zone for gas flow in BF

引用

Journal of Iron and Steel Research International 2007年第6期14卷 1-7页

作者： ZHU Qing-tian CHENG Shu-sen School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

The gas flow from tuyere to raceway zone by blasting involves three distributional zones, such as dripping, cohesive, and lumpy zone. The gas flow distribution in lumpy zone directly affects the gas utilization ration and smooth operation in the blast furnace. However, the furnace closeness brings about great difficulty in the study of high-temperature gas flow. The charging and blasting system affecting the gas flow and whether the top gas flow distribution could reflect its inner condition as well as the furnace state, such as hanging or scaffolding, which have become the main problems for the research on gas flow. Recently, several researches overseas studied gas flow distribution using the numerical simulation method; however, such a research was rare amongst the natives. In this study, the flow model of gas in cohesive and lumpy zone was established using the numerical simulation software and the gas flow distributions with uniform distribution of burden permeability, scaffolding of wall, and nonuniform charge level were analyzed. As a result, the effects of cohesive zone and lower parts on the gas flow are very limited and the charge level largely affects the distribution of top gas flow. Therefore, it was found that the distribution of top gas flow could hardly reflect the inner gas flow. The process is called ＂redistribution＂ effect, which means that the gas flow after passing through the raceway, dripping, and cohesive zone is distributed when it flows into the lumpy zone.

关键词： blast furnace gas flow lumpy zone numerical simulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Explanation of the mechanisms of unsteady gas flow through the turbocharger seal system,including thermal and structural interactions

引用

Propulsion and Power Research 2023年第2期12卷 180-198页

作者： P.Novotný P.Kudlácek J.Vacula Brno University of Technology BrnoTechnicka 2896/261669Czech Republic

gas flow in the seal system can be expected during the operation of a turbocharger and is associated with negative effects on the quality of the lubricant or turbocharger *** flow also affects particulate matter production due to lubricant entrainment in the compressor or *** prediction of gas flow rates depends on many design parameters and the operating conditions of the turbocharger,but sufficiently accurate descriptions of the gas flow mechanisms and their quantification depending on the operating conditions have not yet been *** proposed computational approach simultaneously solves the gas dynamics in the seal system,the heat transfer in the turbocharger rotor-bearing system and the dynamics of the seal rings and rotor,including the *** computational model for the turbocharger of a heavy-duty vehicle engine is experimentally *** mechanisms have major influences on gas mass flow:the gas flow through the thin gap between the moving ring and groove and the flow through the ring *** results show that the importance of these mechanisms depends on several geometrical dimensions of the seal system and the operating conditions of the turbocharger,with a strong connection to the rotor dynamics and thermal load of the *** involving rotor movement or rotor thermal conditions are crucial,and their non-inclusion limits the ability to correctly predict gas mass flow.

关键词： gas blow-by gas flow Heat transfer Rotor dynamics Turbocharger Seal system

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

NEW MODEL OF gas flow PROBLEM IN MULTI-LAYERED gas RESERVOIR AND APPLICATION

引用

Applied Mathematics and Mechanics(English Edition) 1993年第12期14卷 1133-1141页

作者：李笑萍 Daqing Petroleum Institute Anda Helongjiang

In this paper, the new model of the real gas filtration problem has been presented multi-layered gas reservoir, when a gas well output and wellbore storage may be variable, and have obtained the exact solutions of pressure distribution for each reservoir bed under three kinds of typical out-boundary conditions. As a special case, according to the new model have also obtained the qxact solutions of presssure distribution in homogeneous reservoir and is given important application in gas reservoir development.

关键词： multi-layered gas reservoir gas flow model of real gas filtration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

gas flow characteristics in straight silicon microchannels

引用

Chinese Physics B 2002年第9期11卷 869-875页

作者：丁英涛姚朝晖等 DepartmentofEngineeringMechanics TsinghuaUniversityBeijing100084China

Experiments have been conducted to investigate nitrogen gas flow characteristics through four trapezoidal sili-con microchannels with different hydraulic diameters. The volume flow rate and pressure ratio are measured in theexperiments. It is found that the friction coefficient is no longer a constant, which is different from the conventionaltheory. The characteristics are first explained by the theoretical analysis. A simplified rectangular model (rectangularstraight channel model) is then proposed. The experimental results are compared with the theoretical predictions basedon the simplified rectangular model and the two-dimensional flow between the parallel-plate model which was usuallyuse The difference between the experimental data and the theoretical predictions is found in the high-pressure ratiocasesx. The influence of the gas compressibility effect based on the Boltzmann gas kinetic analysis method is studiedto interpret the discrepancy. We discuss two important factors affecting the application extent of different predictionmodels.

关键词： gas flow friction coefficient rectangular model compressibility

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

An integrated approach to study of strata behaviour and gas flow dynamics and its application

引用

International Journal of Coal Science & Technology 2015年第1期2卷 12-21页

作者： Hua Guo Liang Yuan The Commonwealth Scientific and Industrial Research Organisation PO Box 883 Kenmore QLD 4069 Australia Huainan Mining (Group) Co. Ltd. Huainan 232001 China

This paper presents an advanced and integrated research approach to longwall mining-induced strata move- ment, stress changes, fractures, and gas flow dynamics with actual examples of its application from recent studies for coextraction of coal and methane development at Huainan Mining Group in China, in a deep and multi-seam mining environment. The advanced approach takes advantage of the latest techniques in Australia for mine scale geotechnical characterisation, field measurement, monitoring and numerical modelling. Key techniques described in this paper include coal mine site 3D geotechnical characterisation methods, surface deep downhole multi-point extensometers and piezometers for overburden displacement and pore pressure measurements during mining, tracer gas tests for goal gas flow patterns, and advanced numerical modelling codes for coupled coal mine strata, water and gas simulations, and longwall goaf gas ttow investigations. This integrated approach has resulted in significant insights into the complex dynamic imeraction between strata, groundwater, and gas during mining at Huainan Mining Group in recent years. Based on the lindings from the extensive field monitoring and numerical modelling studies, a three-dimensional annular-shaped over-lying zone along the perimeter of the longwall panel was identified for optimal methane drainage during mining.

关键词： Co-extraction of coal and gas Strata behaviour Pore pressure gas flow Annular overlying zone COSflow CFD

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：