检索结果-内蒙古大学图书馆

Probabilistic distribution of initial ejection state of particles in equilibrium sand transport

Kung Cheng Je Wu Li Hsueh Pao/Journal of engineering Thermophysics 2005年第4期26卷 613-616页

作者： Xing, Mao Guo, Lie-Jin State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 China

The equilibrium sand transport is simulated by Lagrange model combined with the probabilistic distributions of initial speed and angle of ejection sand grain in this paper. Five forms of the possible distributions are summarized from the previous study results published in literature. Since the macro-quantities simulated by rational distribution should be coincident well with experimental result, the rationality of the distributions can be tested by comparing the quantities simulated from these distributions with the experimental quantities. Detailed analysis indicates that the distribution of initial speed and angle of ejected grains in equilibrium sand transport should be a monotonous decline function. According to the experimental data a segmented function comprised by an exponential distribution and a normal distribution is suggested in this paper. This distributions is confirmed by further comparison with experimental data.

关键词： Distribution Ejection Equilibrium transport Sand

来源：评论

学校读者我要写书评

暂无评论

Effects of reactant gas flow rates on the current distribution in a PEM fuel cell

引用

Wuhan Ligong Daxue Xuebao/Journal of Wuhan University of Technology 2006年第SUPPL. 2期28卷 601-604页

作者： Shang, De-Hua Zhang, Guang-Sheng Guo, Lie-Jin State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 China

As an important performance diagnosis tool, in-situ measurement of current distribution in PEM fuel cells is helpful for better understanding of internal transport phenomena and optimization of fuel cell structures and operating parameters. With a specially developed current distribution measurement gasket, the effects of reactant gas flow rates on the current distribution in a PEM fuel cell with single serpentine flowfield were investigated. Experimental results show that insufficient hydrogen or air leads to decreased current density along the gas flow direction. Higher reactant gas flow rate favors not only the local performance but also the homogeneity of current distribution. But current distribution almost ceases to change with further increase of hydrogen flow rate when it reaches certain value.

关键词： Current distribution Fuel cell Proton exchange membrane (PEM)

来源：评论

学校读者我要写书评

暂无评论

Dynamics of Internal Jets in the Merging of Two Droplets of Unequal Sizes

Dynamics of Internal Jets in the Merging of Two Droplets of ...

引用

第八届海峡两岸激波与复杂流动学术会

作者： Chenglong Tang Jiaquan Zhao Peng Zhang Chung K.Law Zuohua Huang Department of Mechanical and Aerospace Engineering Princeton University State Key Laboratory of Multiphase Flow and Power Engineering Xi'an Jiaotong University Department of Mechanical Engineering Hong Kong Polytechnic University Center for Combustion Energy Tsinghua University

*** Collision of two droplets in a gaseous environment plays an essential role in many natural and industrial processes,such as raindrop and cloud formation,insecticide spraying,spray painting,and spray combustion in various liquid-fueled *** the most symmetrical event,namely the head-on collision between two identical droplets,it has been experimentally and theoretically-demonstrated that,

关键词： simulation Dynamics of Internal Jets in the Merging of Two Droplets of Unequal Sizes

来源：评论

学校读者我要写书评

暂无评论

Experiments and Predictions for Severe Slugging of Gas-Liquid Two-Phase flows in a Long-Distance Pipeline-Riser System

SSRN

引用

SSRN 2023年

作者： Chang, Yingjie Xu, Qiang Zou, Suifeng Zhao, Xiangyuan Wu, Quanhong Wang, Yechun Thévenin, Dominique Guo, Liejin State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an710049 China Laboratory of Fluid Dynamics and Technical Flows Otto-von-Guericke-Universität Magdeburg Magdeburg39106 Germany

Experiments concerning the flow regimes observed in gas-liquid two-phase flows in a long pipeline-riser system have been carried out and are analyzed in this paper. The test loop with 0.075 m inner diameter consists of a 31. m horizontal pipeline, followed by a 25 m downward-inclined pipe, and finally a 21.5 m riser pipe. An industrial-scale global flow regime map is derived from differential pressure measurements in the riser. Electrical capacitance volume tomography installed in the horizontal section was used to reconstruct the phase interface in order to calculate the average gas void fraction (GVF). An appropriate model for this system is selected by comparing the experimental GVF with different, widely used models. The occurrence of a severe slugging flow (SS) can be well predicted using the model involving additional corrections (taking into account pipeline length, accurate GVF results, and gas density). This study supports the development of a suitable SS prediction model enabling safe design, operation, and control of practical systems. © 2023, The Authors. All rights reserved.

关键词： Pipelines

来源：评论

学校读者我要写书评

暂无评论

Experimental study of liquid slug velocity in horizontal pipe line

引用

Kung Cheng Je Wu Li Hsueh Pao/Journal of engineering Thermophysics 2006年第1期27卷 71-74页

作者： Wang, Xin Guo, Lie-Jin Zhang, Xi-Min Guo, Fu-De State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 China

The velocities of liquid slugs in continuous slug flow were studied experimentally in a 1.3 m long horizontal pipeline. Measurements were performed by cross-correlating the signals of two pairs of probes installed along the pipeline. Correlations of liquid slug velocities with the mixed velocities are presented. It is found that the correlations depend on Froude numbers. At low Froude numbers, the correlation from the measurements of the upstream probes is consistent with that from the measurements of the downstream probes and both correlations agree well with the results of other researchers. But there is difference between the correlation of the upstream probes and that of the downstream probes at high Froude numbers. Compared with the experimental data of other researchers, it is expected that the velocities of liquid slugs are affected by the void fraction in liquid slugs and the evolution of the lengths of liquid slugs and elongated bubbles along pipeline. However, the wake effect may have no influence on the liquid slug velocities.

关键词： Liquid slug velocity Slug flow Slug length Two-phase flow

来源：评论

学校读者我要写书评

暂无评论

Experimental Study and Theoretical Development of Liquid Entrainment in T-Junction with Double Inlets and Single Inlet of Gas Phase

SSRN

引用

SSRN 2023年

作者： Li, Kepiao Shi, Yanggen Zhang, Kui Tian, Wenxi Qiu, Suizheng State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi’an710049 China School of Nuclear Science and Technology Shaanxi Key Laboratory of Advanced Nuclear Energy and Technology Xi'an Jiaotong University Xi’an710049 China

The liquid phase entrainment through vertical-up branch had been analyzed through scaled and full size of experiment since ADS-4 (the fourth-stage Automatic Depressurization System) valve adopted in advanced PWR (Pressurized Water Reactor). Most of the existed studies focus on the single inlet of gas whereas steam may flow from two sides of the T-junction during the blowdown of primary system. Hence the experimental study on liquid entrainment with double end inlets are carried out. The data on the onset of entrainment (OLE) turns out that double end inlets show small difference with single inlet, whereas the entrainment rate research have great difference with single inlet and there is more than 50% error between the data and existing theoretical models. According to the visible flow phenomenon and flow instability, a new entrainment rate model was proposed which can well predict the double-end inlets and single-inlet entrainment phenomenon with the error within ±20%. © 2023, The Authors. All rights reserved.

关键词： Pressurized water reactors

来源：评论

学校读者我要写书评

暂无评论

Improvement on Quantitative Measurement of Fly Ash Contents Using Laser-Induced Breakdown Spectroscopy

引用

Journal of flow Control, Measurement & Visualization 2015年第1期3卷 10-21页

作者： Zhenzhen Wang Yoshihiro Deguchi Hiroaki Watanabe Ryoichi Kurose Junjie Yan Jiping Liu State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an China Graduate School of Advanced Technology and Science The University of Tokushima Tokushima Japan Energy Engineering Research Laboratory The Central Research Institute of Electric Power Industry Kanagawa Japan Department of Mechanical Engineering and Science Advanced Research Institute of Fluid Science and Engineering Kyoto University Kyoto Japan

Contents of fly ash are important factors for the operation of coal-fired plants. Real-time monitoring of coal and fly ash such as unburned carbon in fly ash can be an indicator of the combustion conditions. Because of the strong signal intensity and the relative simplicity of the LIBS (Laser- Induced Breakdown Spectroscopy) technique, LIBS can be applicable for real-time composition measurement of coal and fly ash. This research presented here focused on the clarification of the effects of plasma temperature and coexisting materials on quantitative measurement of fly ash contents. Quantitative capability of LIBS was improved using the proposed plasma temperature correction method. The CO2 effect was also discussed to accurately evaluate unburned carbon in fly ash in exhausts. Using the results shown in this study, quantitative measurement of fly ash contents has been improved for wider applications of LIBS to practical fields.

关键词： Laser-Induced Breakdown Spectroscopy Fly Ash Temperature Correction CO2 Effect

来源：评论

学校读者我要写书评

暂无评论

Method for liquid viscosity coefficient measurement using inclined tube

引用

Kung Cheng Je Wu Li Hsueh Pao/Journal of engineering Thermophysics 2007年第3期28卷 382-384页

作者： He, Mao-Gang Zhang, Ying Wang, Xiao-Fei Zhong, Qiu Li, Hui-Zhen State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 China

In this paper, we provide a method which can be used to measure the viscosity coefficient of the liquid under high-pressure condition and low-boil substances using inclined tube, and measurement system was designed and constructed. The kinematic viscosity coefficients of pure water which is the standard substance to calibrate viscosity measurement system were measured to verify the accuracy and reliability of the experimental system. The measurement results show that the absolute average of relative deviations is 0.65%. Then the kinematic viscosity coefficients of the saturated liquid of the low-boil substance, R1.4a were also measured to detect the measurement system.

关键词： Viscosity

来源：评论

学校读者我要写书评

暂无评论

Heoretical calculation of a continuous preparation system for emulsion

引用

Kung Cheng Je Wu Li Hsueh Pao/Journal of engineering Thermophysics 2013年第1期34卷 91-94页

作者： Wu, Dong-Yin Wang, Li-Bing Wang, Wu-Qiang Wang, Jian Yao, Ji State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 China

This article proceeds a new method which can continuously prepare emulsion by using a venturi tube, to achieve the goal of emulsify diesel oil, methane and water. The diesel oil comes in at the entrance of the venturi tube. The solution of methane and water comes in at the throat of venturi tube and mixes with diesel oil to form emulsion. The preparation system is designed and the structure parameter of the venturi tube is calculated. Then FLUENT is used to do a series of numerical simulation of the flow in the venturi tube under different parameters of spread angle and ratio of length to diameter, thus deciding the best parameters which are 8 degree and 1.25. The basic data for the design of experimental system is provided.

关键词： Methane

来源：评论

学校读者我要写书评

暂无评论

Chemical Kinetics Simulation on Nitrogen Migration Characteristics During Co-Combustion of Ammonia and Coal Under Deeply Fuel-Air Multistage Conditions

SSRN

引用

SSRN 2024年

作者： Dai, Liangxu Wang, Chang'an Hou, Yujie Ma, Guowei Chen, Yongxu Hurera, Abu Zhou, Lei Che, Defu State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power Engineering Xi’an Jiaotong University Xi’an710049 China China Energy Science and Technology Research Institute Co. Ltd. Nanjing210046 China

mmonia, a carbon-free fuel, is attracting an ever-increasing attention. Coal/ammonia co-combustion in coal-fired power plants is considered an effective and fast approach to achieving the global decarbonization goal. However, one bottleneck of the utilization of ammonia fuel is the possible increased NOx emissions. The supply strategy of ammonia can affect the reduction of NOx by NH3. Few studies have explored the influence of ratios of ammonia as a secondary fuel and the secondary air volume on NOx emissions, which could be effective methods to reduce pollution. In this work, a chemical kinetics model was established to study the NOx behaviors during coal/NH3 co-firing in deeply fuel-air multistage conditions. The effects of the ammonia distribution strategies such as the ratio of NH3 as a secondary fuel, the injection position of secondary fuel, and corresponding air distribution with different NH3 co-firing ratios (CR-NH3) on the ammonia reactivity for NOx-reduction were studied. The results show that ammonia should be used as a primary fuel entering the main combustion zone under small CR-NH3 conditions to mitigate the NOx emissions;otherwise, ammonia is inclined to be used as a secondary fuel entering the reduction zone under large CR-NH3 conditions. NOx generation is also found to primarily occur in the burnout zone in fuel-air multistage combustion. Thus, the burnout zone should be given priority to decrease the NOx emissions. With the delay of secondary fuel injection in the reduction zone, the escaping ammonia keeps increasing in the outlet of the reduction zone. Then it is completely burned in the burnout zone, which leads to an increase in NOx emissions. The volume {1. rate of NOx shows a downward trend on the whole with the ratio of secondary air increased. The air distribution can alter the function of the reduction zone in both generating and eliminating NO. The findings can provide some guidance to effectively decrease NOx emissions in coal/NH3 co-fi

关键词： Coal

来源：评论

学校读者我要写书评

暂无评论

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

请选择保存的检索档案：

请选择收藏分类：

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

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

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：