检索结果-内蒙古大学图书馆

Simulation of the PHEBUS FPT-1 experiment using MELCOR and exploration of the primary core degradation mechanism

Annals of Nuclear Energy 2015年 85卷 193-204页

作者： Jun Wang Michael L. Corradini Wen Fu Troy Haskin Yapei Zhang Wenxi Tian Guanghui Su Suizheng Qiu State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an 710049 China College of Engineering The University of Wisconsin-Madison Madison 53706 United States Institute of Nuclear and New Energy Technology Tsinghua University Beijing 100084 China

Core degradation evaluation of probability, progression and consequences of a core degradation accident is critical for evaluation of risk as well as its mitigation. However, research and modeling of severe accidents to date are limited, and their accuracy in predicting severe accident consequences is still insufficient. It is therefore important to explore the mechanisms of core degradation and to develop mitigation measures for severe accidents. PHEBUS FPT1 is a typical and classic core degradation experiment. MELCOR is a world famous severe accident analysis code developed by Sandia National Lab that has seen wide application, a broad user base, and a number of supporting experiments. The PHEBUS experiment was simulated using MELCOR in this paper. Experimental data on, thermal power and steam mass flow rates are used to determine average pressure, energy distribution, molten mass, temperature of the fuel, and hydrogen generation. Data from the PHEBUS experiment and Cho’s calculations are used to compare the average pressure, several fuel temperatures and the hydrogen generation rate. The results confirm the validity of MELCOR’s simulation of the PHEBUS experiment. The temperature distribution of the core is provided. These results are used to determine the mode and behavior of core degradation with the intent of building a foundation for further research.

关键词： PHEBUS FPT1 MELCOR Core degradation

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

Influence of transient thermal response of solid wall on bubble dynamics in pool boiling

引用

Journal of Computational multiphase flows 2014年第3期6卷 313-327页

作者： Zhang, Liang Li, Zhen-Dong Li, Kai Li, Hui-Xiong Zhao, Jian-Fu Beijing100190 China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Shaanxi710049 China Beijing102209 China

Numerical simulation of single bubble pool boiling process including transient thermal response of solid wall is performed using the ghost fluid method and the level set method for the sharp interface representation. The results show that non-physical initial condition in the numerical simulation deeply affects the process of bubble growth, and then multi-cycle simulation is necessary to eliminate its influence. It is shown by the present results that two nucleate criteria, i.e. constant waiting time and constant nucleate superheat, for determining the appearance time for the subsequent bubble lead to the same quasi-steady process of bubble growth if they are matched with each other. A periodically expanding and receding thermal "hollow" can be observed inside solid wall underneath the growing bubble. The recovery of the temperature on the nucleate site and the thermal boundary layer near the heating surface is influenced by transient heat conduction inside solid wall, which can affect evidently bubble thermal dynamics and heat transfer.

关键词： Numerical methods

来源：评论

学校读者我要写书评

暂无评论

Au@SiO_2 core/shell nanoparticle-decorated TiO_2 nanorod arrays for enhanced photoelectrochemical water splitting

引用

Chinese Science Bulletin 2014年第18期59卷 2191-2198页

作者： Jianan Chen Miao Yu Yuhao Wang Shaohua Shen Meng Wang Liejin Guo International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi’an Jiaotong University School of Chemical Engineering and Technology Harbin Institute of Technology

To improve the separation efficiency of photoinduced charge carries,Au@SiO2nanoparticles(NPs)with core–shell structure were loaded onto the surface of TiO2nanorods grown on fluorine-doped tin oxide substrate by a facile two-step *** resulted Au@SiO2/TiO2photoanodes were characterized by X-ray diffraction,scanning electron microscopy,transmission electron microscopy,as well as photoelectrochemical *** with pristine TiO2nanorod film,the Au@SiO2/TiO2films showed remarkable enhancement in photoelectrochemical water splitting,with incident photonto-current conversion efficiency increasing from 31%to37%at 380 nm at 0.7 V versus saturated calomel *** could be interpreted by the effect of metallic surface plasmon resonance of Au@SiO2NPs,which would generate an intense electromagnetic field with spatially nonhomogenous distributed *** a result,the charge carriers generated in the near-surface region of TiO2nanorods could be easily *** modification method based on the effect of metallic surface plasmon resonance for promoted charge carrier separation provides a promising way to develop semiconductor photoelectrodes with high solar water-splitting performance.

关键词：二氧化硅纳米粒子二氧化钛纳米棒电解水表面等离子体共振效应纳米颗粒金属 TiO2薄膜

来源：评论

学校读者我要写书评

暂无评论

Experimental and modeling study on auto-ignition of DME/ n -butane blends under engine relevant pressure

Experimental and modeling study on auto-ignition of DME/ n -...

引用

SAE 2014 World Congress and Exhibition

作者： Jiang, Xue Zhang, Yingjia Pan, Lun Man, Xingjia Huang, Zuohua State Key Laboratory of Multiphase Flow in Power Engineering Xi'An Jiaotong University Xi'an 710049 China

In this study, the ignition delay times of DME/n-C4H 10 fuel blends (neat DME, 50/50 and neat n-C4H 10) diluted with argon were measured behind reflected shock waves. The experiments were performed in the temperature range of 1250 - 1600 K, at pressure of 2.0 MPa and equivalence ratios from 0.5 to 2.0. A latest kinetic mechanism NUIG Aramco Mech 1.3 was validated against the present ignition data and used to conducted chemical kinetic analysis. Different equivalence-ratio- dependent was exhibited at different temperature regimes for DME, n-C 4H10, and their blend. Fuel flux analysis, sensitive analysis and mole fraction analysis were carried out for understanding the interaction between the ignition chemistries of DME and n-C4H 10. Copyright © 2014 SAE International.

关键词： Shock waves

来源：评论

学校读者我要写书评

暂无评论

Heat transfer characteristics of hydrocarbon fuel in a horizontal small tube under different pressures 11

Heat transfer characteristics of hydrocarbon fuel in a horiz...

引用

AIAA AVIATION 2014 -11th AIAA/ASME Joint Thermophysics and Heat Transfer Conference 2014

作者： Yang, Zhuqiang Bi, Qincheng Guo, Yong Liu, Zhaohui Jiang, Lei State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi' an 710049 China

ISBN: (数字)9781624102813

ISBN: (纸本)9781624102813

Experiments for heat transfer of a kerosene hydrocarbon fuel in a small horizontal tube have been conducted at subcritical and supercritical pressures. Parameters included the pressure of 2.0-5.0 MPa, mass flux of 822-2466 kg/ (m2·s) and heat flux up to 1500 kW/m2. The wall temperature and heat transfer performance at various operating conditions were captured in the experiments. Based on the results, the normal, improved and deteriorated heat transfer characteristics of the fuel were analyzed in detail. The effects of heat flux, pressure and mass flux on the heat transfer were discussed respectively. The heat transfer performed better when working pressure approached critical pressure. The deterioration in the large change of thermophysical properties region didn't occur at supercritical pressures. In the test, the increase of mass flux could enhance the heat transfer. But the effect of the enhancement decreased with mass flux increase. As to the pressure drop characteristics, low pressure and high mass flux both contributed to the increase of flow resistance.

关键词： Heat flux

来源：评论

学校读者我要写书评

暂无评论

Convective heat transfer characteristics of supercritical hydrocarbon fuel in small non-circular cross-section Channels 11

Convective heat transfer characteristics of supercritical hy...

引用

AIAA AVIATION 2014 -11th AIAA/ASME Joint Thermophysics and Heat Transfer Conference 2014

作者： Guo, Yong Yang, Zhuqiang Jiang, Lei Liu, Zhaohui Bi, Qincheng State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 China

ISBN: (数字)9781624102813

ISBN: (纸本)9781624102813

Convective heat transfer characteristics of supercritical pressure hydrocarbon fuel were experimentally investigated in electrically heated small non-circular channels with hydraulic diameter ranging from 2.00 to 3.00 mm. In this research, the system pressure and fuel mass velocity were maintained at supercritical (3.0 MPa) and 840.0 kg/(m2·s), while fuel inlet temperature varied from 200.0 ~ 450.0 °C. Heat transfer characteristics of various cross-section channels were obtained in view of the temperature profiles on the channel outside surface. Experimental results were compared among different non-circular channels. The effects of inlet fuel temperature, heat flux, aspect ratio or length to diameter ratio on the convective heat transfer characteristics were discussed. Due to the varieties of length to diameter ratio, the unique heat transfer characteristics of non-circular cross-section channels seemed to make them suitable for the application of hypersonic vehicle. However, this study did not consider the pyrolytic reaction in the high temperature range. The coking characteristics of small non-circular channels under high temperature may trade off the benefits acquired in the heat transfer characteristics.

关键词： Aspect ratio

来源：评论

学校读者我要写书评

暂无评论

Experimental and modeling study on ignition delay times of dimethyl ether/ n -butane blends at a pressure of 2.0 MPa

Experimental and modeling study on ignition delay times of d...

引用

作者： Jiang, Xue Zhang, Yingjia Man, Xingjia Pan, Lun Huang, Zuohua State Key Laboratory of Multiphase Flow in Power Engineering Xi'An Jiaotong University Xi'an 710049 China

In this study, the ignition delay times of dimethyl ether (DME)/n-C 4H10 fuel blends, neat DME, and neat n-C4H 10 diluted with argon were measured behind reflected shock waves. The experiments were performed in the temperature range of 1100-1600 K, at a pressure of 2.0 MPa, and equivalence ratios from 0.5 to 2.0. A latest kinetic mechanism NUIG Aramco Mech 1.3 was validated against the measured ignition data and used to conduct the chemical kinetic analysis. Results showed that different equivalence ratio-dependent behaviors were exhibited at different temperature regimes for DME, n-C4H10, and their blend. The ignition delay time of neat n-C4H10 was increased with an increase in the equivalence ratio. A strong inhibiting trend was exhibited at high temperatures. For the neat DME, however, an opposite influencing tendency from the equivalence ratio was presented in comparison to that on n-C 4H10. Ignition promotion becomes significant at relatively low temperatures. A 50% DME/50% n-C4H10 blend show a combined behavior of both n-butane and DME. Fuel reaction flux analysis, sensitive analysis, and mole fraction analysis were conducted for the understanding of the interaction between the ignition chemistries of DME and n-C4H10 at a pressure of 2.0 MPa. © 2014 American Chemical Society.

关键词： Ethers

来源：评论

学校读者我要写书评

暂无评论

Visualization investigation of secondary flow on heat transfer deterioration in horizontal heat tube 22

引用

2014 22nd International Conference on Nuclear engineering, ICONE 2014

作者： Wu, Chao Li, Hui-Xiong Qian, Zhang State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an Shaanxi China

ISBN: (纸本)9780791845905

Mixed convection heat transfer in heated tubes has been studied extensively in the past decades, which is widely used in various industrial fields such as cooling of a nuclear reactor core. The secondary flow, which is induced by buoyancy force, has been found in previous research to have profound influence on the heat transfer difference on circumferential position and occurrence of heat transfer deterioration in horizontal heated channel. Therefore, understanding the secondary flow velocity field has important implications to prevent heat transfer deterioration and ensure the safe operation of nuclear power plants. Numerical methods have been adopted in literature to analyze the complex interaction between secondary flow and heat transfer deterioration. However, to the knowledge of the author, experimental measurement of secondary flow in the radial cross-section of a horizontal tube does not exist.. Copyright © 2014 by ASME.

关键词： Numerical methods

来源：评论

学校读者我要写书评

暂无评论

Flame-front instabilities of outwardly expanding isooctane/ n -butanol blend-air flames at elevated pressures

Flame-front instabilities of outwardly expanding isooctane/ ...

引用

作者： Zhang, Xinyi Tang, Chenglong Yu, Huibin Huang, Zuohua State Key Laboratory of Multiphase Flow in Power Engineering Xi'An Jiaotong University Xi'an 710049 China

Experiments were conducted in a constant volume bomb filled with isooctane/n-butanol blend-air mixtures over a wide range of n-butanol blending ratios, equivalence ratios, and initial pressures. High-speed schlieren photography was used to measure the critical radius for the onset of flame-front instability. Results show that, for a given n-butanol blending ratio, cellular instabilities appear earlier and the critical Peclet number, which represents the onset of instability, is decreased with the increase of the initial pressure and equivalence ratio. Under fuel-rich conditions, the critical Peclet number increases with the increase of the n-butanol blending ratio. Theoretical calculation of the critical Peclet number was also conducted to interpret the effects of n-butanol on the flame-front instabilities of the blends. Results show that, for rich mixture conditions, with the increase of the n-butanol blending ratio, the overall activation energy of the mixtures is decreased and, thus, the thermal-diffusional instabilities are suppressed. While under fuel-lean conditions, the thermal-diffusional instabilities are favored. As a consequence, with an increasing n-butanol blending ratio, the critical Peclet number is expected to be decreased under fuel-lean conditions and increased under fuel-rich conditions. © 2014 American Chemical Society.

关键词： Mixtures

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：