检索结果-内蒙古大学图书馆

Emission Characteristics and Axial Flame Temperature Distribution of a Circumferential Reverse flow Combustor

Journal of Energy and power {1. 2010年第7期4卷 9-14页

作者： C. Dong Q.L. Zhou X.G. Zhang P. Sun T.M. Xu S.E. Hui Q.X. Zhao State Key Laboratory of Multiphase Flow in Power Engineering Xi ＇an Jiaotong University Xi ＇an 710049 China

In partially premixed combustion of gas turbine, the combustion temperature should be lowed in order to reduce NOx. One solution is lean premixed combustion. However, the problem is that large excess air ratio may make the combustion unstable. A novel combustor with circumferential reverse flow of fuel gas is proposed for settling this problem. A 1. kw furnace is established to test performance of this combustor. Three factors such as primary air ratio, position of secondary air, total excess air ratio are studied. The emission characteristics and axial flame temperature distribution are studied. Basing on experimental results, the axial flame temperature and NOr emission increase with primary air ratio and axial length of second stream, and decrease with total excess air ratio. When the total excess air ratio is larger than 1.05, the combustor presents a lower temperature field and much lower NOx emission （less than 1. ppm）.

关键词： Partially premixed combustor secondary air distributor NOx emission axial flame temperature experimentalinvestigation.

来源：评论

学校读者我要写书评

暂无评论

Experimental Study of Falling Film on the Outside of Horizontal Tube

引用

AIP Conference Proceedings 2010年第1期1207卷 238-243页

作者： L. B. Yan H. X. Li B. Guo Y. Q. Zhang Z. Zhang Y. F. Zhang State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an 710049 China

Evaporating falling film on horizontal tubes has been widely used in desalinization, refrigeration, chemical process industries, and so on. In this paper, the flow characteristics of falling film outside horizontal tubes in horizontal air flows was studied theoretically and experimentally. Two low patterns of the falling film, i.e., droplet flow pattern and columnar flow pattern, were considered. Effects of the velocity of airflow, the flux of falling film flow, the external diameter of tube and the surface property of tube on the falling film flowing characters were investigated. Experimental study indicated that, in a definite flow scale, as the flow increased, the diameters of falling droplets and falling columns of the liquid enlarged, and the liquid film became thick and the area covered by the liquid film increased. As the air velocity increased, the offset of the droplet and the column to the top of the tube enlarged, and the rate of increase come down until it complete depart from the the top of the horizontal tube. Besides, a theoretical model was established about the offset of the droplet and liquid column from the top of the tube under the force of the horizontal air flows, and the model was validated by a comparison between the numerical predictions and experimental data.A further analysis about the excursion law of falling film flow outside horizontal tube was also made at the last paprt of the paper.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Experimental Research on the Performance of Exhaust Steam Reclaim Device With a Swirling flow Vane

引用

AIP Conference Proceedings 2010年第1期1207卷 374-379页

作者： X. L. Li J. J. Yan P. F. Zhang J. J. Yang J. P. Liu State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University P.R. China

This paper experimentally studied the performance of exhaust steam reclaim device with a swirling flow vane at different inlet water pressures, temperatures, different inlet steam pressures and different distances between the throat and spout. The results indicated that the injection coefficient decreased as the inlet water pressure and temperature increased, respectively. There is a best distance between the throat and spout which makes the injection coefficient reached to its maximal value at the same experimental pressure and temperature, and the value equals to 1.0 mm in our experimental system. The resistance coefficient has a minimum value which makes the device have the highest outlet water pressure. Compared with the device without a swirling flow vane, it improves the heating performance for higher injection coefficient and exergy efficiency.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Slagging characteristics on the superheaters of a 1. MW biomass-fired boiler

Slagging characteristics on the superheaters of a 12 MW biom...

引用

作者： Niu, Yanqing Tan, Hongzhang Ma, Lin Pourkashanian, Mohamed Liu, Zhengning Liu, Yang Wang, Xuebin Liu, Haiyu Xu, Tongmo State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power Engineering Xian Jiaotong University Xian 710049 China School of Process Environmental and Materials Engineering University of Leeds Leeds LS2 9JT United Kingdom

In an attempt to understand the problem of severe slagging in biomass-fired boilers, slags formed on the fourth-, second-, and first-stage superheaters in a 1. MW biomass-fired grate furnace have been collected, sampled, and analyzed using X-ray fluorescence (XRF) and X-ray diffraction (XRD) techniques. The slag collected on each superheater has a unique morphology and structure. The slag on the fourth-stage superheater is loose and porous, while on the secondary and the primary superheaters, the slag shows a clear layered structure of different colors and levels of hardness. Aluminosilicate is the major component in the slag on the fourth-stage superheater, which is formed by Si, Al, and alkali species. On both the secondary and primary superheaters, the sticky sylvine, potassium calcium sulfate, and aphthitalite in the bottom layer trap coarse, large particles, resulting in further slagging. In the alternating layers, the particles containing high concentrations of K, Na, and Cl form the initial deposit layer, the yellow layer in the secondary superheater. Then, it traps the coarse, large particles containing high Si, Al, Ca, Mg, and Fe to form the brown layer. Similarly, the particles in the pale-yellow layer of the primary superheater containing high concentrations of K, Na, and Cl form the initial deposit layer, and then, it traps the coarse, large particles containing high Si, Al, Ca, Mg, and Fe to form the black layer. Accompanied by the periodic blowing, the alternating layer is formed and the slag gradually becomes thicker. © 201. American Chemical Society.

关键词： Iron

来源：评论

学校读者我要写书评

暂无评论

THE VELOCITY FIELD OF multiphase {1. AND EFFICIENCY OF BIOLOGICAL AERATION FILTER

引用

Journal of Hydrodynamics 2010年第2期22卷 260-264页

作者： CHENG Wen HU Bao-wei YANG Chun-di CHENG Wen-juan Environment Research Institute Xian University of Technology Xi＇an 710048 China State Key Laboratory of Multiphase Flow in Power Engineering Xi＇ an Jiaotong University Xi＇an 710049 China Key Laboratory of Northwest Water Resources and Environmental Ecology of Education Ministry Xi＇anUniversity of Technology Xi＇an 710048 China Yuanpei College Shaoxing University Shaoxing 312000 China Environment Research Institute Xi＇an University of Technology Xi＇an 710048 China

Aeration is an important factor affecting the biological aeration *** a set of experiment device specially designed for the purpose,and the particle image velocimetry technique,the velocity field of the gas-liquid two-phase flow is studied under different *** various simulated aeration {1.s were actually applied to the experimental device of sewage treatment,and the results of the numerical simulation were *** final experimental results indicate that the most efficient {1. occurs when the ratio of water in aeration tank h / w =1.the diameter of capillary tubes d=0.6mm and the velocity of bubbles v=0.3m/s.

关键词： ratio of water diameter of capillary tube bubbles velocity sewage disposal efficiency

来源：评论

学校读者我要写书评

暂无评论

Exergy analysis of solar dynamic closed Brayton cycle for space applications

引用

Taiyangneng Xuebao/Acta Energiae Solaris Sinica 2010年第3期31卷 351-356页

作者： Chen, Shuangtao Hou, Yu Chen, Liang State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 China School of Energy and Power Engineering Xi'an Jiaotong University Xi'an 710049 China

Exergy analysis of solar dynamic closed Brayton cycle (SDCBC) for space applications was presented in this paper. An integrated model for the system and specific models for its components were proposed. Influence of main parameters on system exergy efficiency was discussed. The results shown the efficiencies of expander, compressor, and regenerating temperature of the regenerator have significant influence on the exergy efficiency of SDCBC system. Therefore, besides the enhancement of component efficiencies, the matching among components of SDCBC system should be also taken into account. Moreover, it would be always desirable to enhance the effectiveness of recuperator within the requirements of flow resistance and system weight.

关键词： Space applications

来源：评论

学校读者我要写书评

暂无评论

Numerical simulation of a buried hot crude oil pipeline during shutdown

引用

Petroleum Science 2010年第1期7卷 73-82页

作者： Xu Cheng Yu Bo Zhang Zhengwei Zhang Jinjun Wei Jinjia Sun Shuyu Beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum Beijing 102249China Zhejiang Department Preparatory Team PetroChina West East Gas Pipeline Company Hangzhou Zhejiang 310000 China State Key Laboratory of Multiphase Flow in Power Engineering Xi＇an Jiaotong University Xi＇an Shaanxi 710049 China Department of Mathematical Sciences Clemson University Clemson SC 29634-0975 USA

In this paper a mathematical model is built for a buried hot crude oil pipeline during shutdown, and an unstructured grid and polar coordinate grid are respectively applied to generating grids for the soil region and the three layers in the pipe （wax layer, pipe wall, and corrosion-inhibiting coating）. The governing equations are discretized using the finite volume method. The variations in temperatures of static oil and soil were investigated during pipeline shutdown in both summer and winter, in which some important parameters of the soil and crude oils of a Northeast pipeline are employed.

关键词： Moving boundary stagnation point equivalent thermal conductivity thermal influence region unstructured grid

来源：评论

学校读者我要写书评

暂无评论

Experimental study on the characteristics of weak corrosive surfactant drag reducer

Experimental study on the characteristics of weak corrosive ...

引用

1.th International Conference on engineering, Science, Construction, and Operations in Challenging Environments - Earth and Space 201.

作者： Su, Wen-Tao Li, Feng-Chen Dong, Yong Cai, Wei-Hua Jiao, Li-Fang Wei, Jin-Jia Yu, Bo School of Energy Science and Engineering Harbin Institute of Technology Harbin 150001 China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiao Tong University Xi'an 710049 China Beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum Beijing 102249 China

ISBN: (纸本)9780784410967

Experimental study on drag-reducing characteristics of a zwitterionic surfactant additive (C20H43NO) in a circulation system has been carried out. It was based on the optimum concentration, temperature effect and the characteristics of resisting shear in DN27.5 pipeline. The results showed that C20H43NO additive has a significant drag-reducing effect depending on concentration and temperature. The most effective concentration in the tested flow loop was 900ppm at 60°C. The temperature range of the drag-reducing effect was in the range of 40 ∼ 70°C. The maximum drag reduction (DR) of 900ppm C20H 43NO aqueous solution was 77% at the beginning of circulation with system running between 41.C and 43°C. The drag-reducing effect does not decrease remarkably after the circulation system ran for a period of seven hours, but reduces to only 5% of DR after a period of twenty-three hours. In order to study the drag-reducing characteristics of C20H 43NO aqueous solution in the practical district heating system, the experiments with C20H43NO aqueous solution flow in different inner-diameter pipelines including DN50 and DN1.0 with rough wall were performed. The results indicated that the optimum drag-reducing concentrations are 1.00ppm and 2500ppm at 45∼50°C in the DN50 and DN1.0 circular pipes, respectively. Finally, the technique of drag-reducing additive applying into the district heating system is discussed. And some problems in the practical application were brought forward, such as, the poor life-span of surfactant, the instabilities of drag-reducing effect and the inherent corrosion of additive itself. According to these problems, the corrosion research of C 20H43NO aqueous solution was also conducted based on immersion method. The results show that: C20H43NO aqueous solution is weakly corrosive for iron-based metallic pipe comparing with CTAC aqueous solution and water. © 201. ASCE.

关键词： Pipelines

来源：评论

学校读者我要写书评

暂无评论

Nitrogen, sulfur, and chlorine transformations during the pyrolysis of straw

Nitrogen, sulfur, and chlorine transformations during the py...

引用

作者： Wang, Xuebin Si, Jipeng Tan, Houzhang Ma, Lin Pourkashanian, Mohamed Xu, Tongmo State Key Laboratory of Multiphase Flow in Power Engineering Xian Jiaotong University Xian 710049 China Centre for Computational Fluid Dynamics School of Process Environmental and Materials Engineering University of Leeds LS2 9JT United Kingdom

Transformation of nitrogen, sulfur, and chlorine during straw pyrolysis at temperatures from 35 to 1.50 &#1.6;C was investigated by using the coupled thermogravimetry-differential scanning calorimetry-mass spectrometr... 详细信息

Transformation of nitrogen, sulfur, and chlorine during straw pyrolysis at temperatures from 35 to 1.50 °C was investigated by using the coupled thermogravimetry-differential scanning calorimetry-mass spectrometry (TG-DSC-MS) techniques and compared with that of coal. The characteristics of the residual solid char from the straw were analyzed using x-ray diffraction (XRD). Results show that all the nitrogen species (HCN, NH3, HNCO, and CH 3CN), chloric species (HCl and Cl2), and sulfur species (SO2, H2S and COS) began to release from straw from 200 °C, compared with 350 °C for the case of coal. Most of the gaseous species from the straw were released in the form of a sharp peak, compared with the coal which has a much wider peak. NH3 and HNCO were the primary nitrogen species for both straw and coal;however for the straw the amount of NH3 released was much higher than that of HNCO. Sulfur species from the straw pyrolysis are sparse, and there was only a little COS released. During coal pyrolysis no COS was detected at all and H2S was mainly formed at 500 °C∼600 °C. SO2 was released in three stages (300-500 °C, 500-600 °C and 1.00-1.50 °C), and the largest SO 2 emission was found at high temperatures due to the decomposition of sulfate. The major chloric species from the pyrolysis of both straw and coal was HCl, and the ion current intensity of Cl2 was very low. There was a critical temperature of around 800 °C, beyond which most of the chlorine would be released. © 201. American Chemical Society.

关键词： Pyrolysis

来源：评论

学校读者我要写书评

暂无评论

Evaluating the effect of dislocation on the photovoltaic performance of metamorphic tandem solar cells

引用

Science China(Technological Sciences) 2010年第9期53卷 2569-2574页

作者： ZHANG Han1.CHEN NuoFu2,3,WANG Yu1.ZHANG XingWang1.YIN ZhiGang1.SHI HuiWei1.WANG YanSuo1.HUANG TianMao1.BAI YiMing2 & FU Zhen1. key {1. of Semiconductor Materials Science,Institute of Semiconductors,Chinese Academy of Sciences,P.O.Box 91.,Beijing 1.0083,China 2 School of Renewable Energy engineering,North China Electric power University,Beijing 1.2206,China 3 state key {1. of Silicon Materials,Zhejiang University,Hangzhou 31.027,China 1. Key Laboratory of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences P.O. Box 912 Beijing 100083 China2. School of Renewable Energy Engineering North China Electric Power University Beijing 102206 China3. State Key Laboratory of Silicon Materials Zhejiang University Hangzhou 310027 China

The photovoltaic conversion efficiency for monolithic GaInP/GaInAs/Ge triple-junction cell with various bandgap combination (300 suns,AM1.5d) was theoretically *** impressive improvement on conversion efficiency was observed for a bandgap combination of 1.708,1.1.4,and 0.67 eV.A theoretical investigation was carried out on the effect of dislocation on the metamorphic structure’s efficiency by regarding dislocation as minority-carrier recombination *** results showed that only when dislocation density was less than 1.6×1.6 cm-2,can this metamorphic combination exhibit its efficiency advantage over the fully-matched *** addition,we also briefly evaluated the lattice misfit dependence of the dislocation density for a group of metamorphic triple-junction system,and used it as guidance for the choice of the proper cell structure.

关键词： tandem solar cell theoretical efficiency dislocation buffer layers

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：