检索结果-内蒙古大学图书馆

热能动力工程 2016年第9期31卷 52-57,133-134页

作者：陈文朴李春叶舟缪维跑上海理工大学能源与动力工程学院上海200093 Shanghai City Key Laboratory on Multi-phase Flow and Heat Transfer in Power Engineering

本文为研究叶片铺层参数对叶片动态特性的影响,防止叶片产生共振,改善叶片力学特性,建立了1.5 MW风力机叶片的有限元模型,通过改变铺层角度和铺层纤维比例实现多种不同层合板结构的叶片铺层,并对上述各种铺层叶片结构进行了模态分析,获... 详细信息

本文为研究叶片铺层参数对叶片动态特性的影响,防止叶片产生共振,改善叶片力学特性,建立了1.5 MW风力机叶片的有限元模型,通过改变铺层角度和铺层纤维比例实现多种不同层合板结构的叶片铺层,并对上述各种铺层叶片结构进行了模态分析,获得了各模型的前六阶固有频率和振型,分析了铺层参数影响叶片动态特性的原因。结果表明:复合材料具有显著各向异性,通过改变铺层角度能影响固有频率大小;叶片低阶振型以挥舞和摆振为主,增加0°铺层比例能提高低阶固有频率;叶片高阶模态出现扭转,45°铺层能提高叶片抗扭能力,有利于增加高阶固有频率。

关键词：风力机叶片气动弹性剪裁模态

来源：评论

学校读者我要写书评

暂无评论

Research on characteristics of fluid-induced vibration for short labyrinth seals

引用

JOURNAL OF VIBROengineering 2016年第3期18卷 1811-1823页

作者： Zhang, Wanfu Yang, Jiangang Li, Chun Dai, Ren Yang, Ailing Univ Shanghai Sci & Technol Sch Energy & Power Engn Shanghai 200093 Peoples R China Shanghai Key Lab Multiphase Flow & Heat Transfer Shanghai 200093 Peoples R China Southeast Univ Natl Engn Res Ctr Turbogenerator Vibrat Nanjing 210096 Jiangsu Peoples R China

Short seal (e.g. shroud seal) is a key component for the safe and reliable operation of a turbine unit. This paper sets up the three dimensional numerical model of a short labyrinth seal and analyzes its characteristics of the fluid-induced force. Results show that the tangential fluid-induced force increases almost linearly as the rotational speed increases. The sign of the radial fluid-induced force changes as the rotational speed increases. For higher inlet pressure, a more dramatic increase can be found for both the tangential and radial fluid-induced force. A transition speed range was found that the magnitude of the radial fluid-induced force at higher inlet pressure became less than that at lower inlet pressure. For each seal cavity, the peak pressure location had a shift away from the minimum clearance location as the rotational speed increased. This shift also existed in the axial direction. The effect of the rotational speed on the fluid-induced force became more remarkable for the longer seal with many cavities. Both the radial and tangential fluid-induced force increased with the increasing preswirl ratio. However, the two forces decreased with the increasing preswirl ratio when the inlet total pressure was kept as a constant value. In the end, the critical preswirl ratio which corresponds to zero tangential fluid-induced force was calculated, and results show that a smaller magnitude of the preswirl ratio will be needed to offset the effect of rotational speeds at higher inlet pressures. The inlet preswirl generated a majority of the tangential force for short seals.

关键词： seal fluid-induced force computational fluid dynamics (CFD) preswirl

来源：评论

学校读者我要写书评

暂无评论

Numerical investigation of the yawed wake and its effects on the downstream wind turbine (vol 8, 033303, 2016)

引用

JOURNAL OF RENEWABLE AND SUSTAINABLE ENERGY 2016年第5期8卷 033303-1-033303-17页

作者： Miao, Weipao Li, Chun Yang, Jun Xie, Xiaoyun Univ Shanghai Sci & Technol Sch Energy & Power Engn Shanghai 200093 Peoples R China Shanghai Key Lab Multiphase Flow & Heat Transfer Shanghai 200093 Peoples R China Xihua Univ Lab Fluid & Power Machinery Jinniu Dist 610000 Sichuan Peoples R China Shanghai Behr Thermal Syst Co Shanghai 201206 Peoples R China

A numerical simulation for the wake deviation effect in a wind farm is carried out using the full rotor model of the National Renewable Energy laboratory 5?MW wind turbine. The downstream wind turbine decreases its performance significantly due to the upstream wake interference. To reduce this effect, a control strategy based on the yaw angle is adopted to skew the trajectory of an upstream wake, thereby avoiding the downstream wind turbine and improving the efficiency of whole wind farm power generation. In this paper, the commercial CFD software STAR-CCM+ was used to simulate the wind farm which contains two tandem wind turbines operating in the atmospheric boundary layer condition. The results show that the wind farm's total power increases when the upstream wind turbine applies a yaw angle intentionally. According to the analysis of velocity contours, wake centerlines, and vortex structures, a counter-rotating blade tip vortex pair is observed to be responsible for the wake deviation effects concentrated on the hub height, which reveals that the influence of a yawed wake on the downstream wind turbine may be slightly underestimated.

关键词： Wind turbines Rotating flows Wind farms Turbulence simulations Aerodynamics

来源：评论

学校读者我要写书评

暂无评论

Prediction of thermal performance of radiative radial fin with temperature-dependent thermal conductivity using spectral collocation method

引用

Journal of Computational and Theoretical Nanoscience 2016年第9期13卷 5822-5831页

作者： Ma, Jing Sun, Ya-Song Li, Ben-Wen Key Laboratory of Shaanxi Province for Development and Application of New Transportation Energy School of Automobile Chang'an University Xi'an710064 China Beijing Key Laboratory of Multiphase Flow and Heat Transfer for Low Grade Energy North China Electric Power University Beijing102206 China Institute of Thermal Engineering School of Energy and Power Engineering Dalian University of Technology Dalian116024 China

Spectral collocation method (SCM) is developed to solve coupled radiation and conduction in radiative radial fin with temperature-dependent thermal conductivity and volumetric heat generation. In this approach, energy conservation equation is discretized by SCM, and a particular algorithm is proposed to alleviate the nonlinearity of energy conservation equation. Numerical results by SCM are compared with available results in the literature, which indicate that SCM can provide high accuracy for combined radiative and conductive heat transfer in radiative radial fin, and the integral averaged relative error decreases exponentially with the increasing number of collocation points. Meanwhile, the effects of various parameters on the thermal performance, such as dimensionless thermal conductivity coefficient, radiation-conduction parameter, dimensionless ambient temperature, dimensionless radiation sink temperature and dimensionless volumetric heat generation are also investigated. Copyright © 2016 American Scientific Publishers All rights reserved.

关键词： Fins (heat exchange)

来源：评论

学校读者我要写书评

暂无评论

The poisoning effect of heavy metals doping on Mn/TiO₂ catalyst for selective catalytic reduction of NO with NH₃

引用

JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL 2015年 407卷 1-7页

作者： Guo, Rui-tang Wang, Qing-shan Pan, Wei-guo Chen, Qi-lin Ding, Hong-lei Yin, Xue-feng Yang, Ning-zhi Lu, Chen-zi Wang, Shu-xian Yuan, Yi-chao Shanghai Univ Elect Power Sch Energy Source & Mech Engn Shanghai Peoples R China Shanghai Engn Res Ctr Power Generat Environm Prot Shanghai Peoples R China Inner Mongolia Univ Environm & Resource Coll Hohhot Inner Mongolia Peoples R China Shanghai Key Lab Multiphase Flow & Heat Transfer Shanghai Peoples R China

Heavy metals have been proven to be of deactivation effect on SCR catalyst. In this paper, the poisoning effect of heavy metals (Zn and Pb) on Mn/TiO2 catalyst was investigated based on experimental and theoretical study. It was found that both of Zn and Pb had a poisoning effect on Mn/TiO2 catalyst and the poisoning effect of Zn was more obvious. The characterization results indicated that the doping of heavy metals on Mn/TiO2 surface would lead to a great decrease of reducibility, surface acidity and NO adsorption ability. The results of XPS characterization revealed the decrease of Mn4+ atomic concentration and chemisorbed oxygen species caused by the doping of heavy metals. Based on the above mentioned unfavorable properties, the doping of heavy metals would cause a serious deactivation of Mn/TiO2 catalyst. From the results of OFT calculations, it could be concluded that the doping of heavy metals on Mn/TiO2 catalyst resulting in a great decrease of NH3 adsorption capacity and NO adsorption ability, which agrees well with the experimental results. (C) 2015 Elsevier B.V. All rights reserved.

关键词： Mn/TiO2 catalyst Deactivation Zn Pb Characterization DFT

来源：评论

学校读者我要写书评

暂无评论

The influence of F and Cl on Mn/TiO₂ catalyst for selective catalytic reduction of NO with NH₃: A comparative study

引用

CATALYSIS COMMUNICATIONS 2015年 71卷 84-87页

作者： Wang, Peng Wang, Qing-shan Ma, Xin-xia Guo, Rui-tang Pan, Wei-guo Shandong Univ Natl Engn Lab Coal Fired Pollutants Emiss Reduct Jinan 250100 Peoples R China Shanghai Univ Elect Power Sch Energy Source & Mech Engn Shanghai Peoples R China Shanghai Engn Res Ctr Power Generat Environm Prot Shanghai Peoples R China Shanghai Key Lab Multiphase Flow & Heat Transfer Shanghai Peoples R China

The effect of F and Cl on Mn/TiO2 catalyst for selective catalytic reduction of NO with NH3 was investigated in this study. It was found that the doping of F or Cl has a deactivation effect on Mn/TiO2 catalyst. And the poisoning effect of Cl is more serious than that of F. The characterization results showed that the decrease of BET surface area, the increase of crystallinity, the reduced reducibility and surface acidity, and the decreased concentrations of surface Mn4+ and chemisorbed oxygen should be responsible for the deactivation of Mn/TiO2 catalyst by the doping of F or Cl. (C) 2015 Elsevier B.V. All rights reserved.

关键词： Mn/TiO2 catalyst Deactivation F Cl Mechanism

来源：评论

学校读者我要写书评

暂无评论

Investigation on liquid film of urea-water solutions with diode laser absorption spectroscopy

引用

EXPERIMENTS IN FLUIDS 2015年第4期56卷 73-73页

作者： Yang, Huinan Guo, Xiaolong Zhou, Wu Chen, Benting Hu, Jiarui Su, Mingxu Cai, Xiaoshu Univ Shanghai Sci & Technol Sch Energy & Power Engn Shanghai 200093 Peoples R China Univ Shanghai Sci & Technol Shanghai Key Lab Multiphase Flow & Heat Transfer Shanghai 200093 Peoples R China

Measurement of multiparameter of liquid films (e.g., film thickness and concentration) is very important to understand the film formation processes in industrial applications. Here, a novel diode laser absorption spectroscopy (DLAS) sensor was developed to simultaneously measure the liquid film thickness and concentration of urea-water solutions by forming the transmittance ratio at two wave-number positions. The performance of the sensor employed two diode lasers (6613.25 and 7187.50 cm(-1)) was first validated using a calibration tool providing liquid film of urea-water solutions with known film thickness (100-1000 mu m) and mass fractions (5-50 wt%), and then, the sensor was applied to study a free-falling film of urea-water solutions on a vertical transparent quartz plate. Shadowgraph images were simultaneously taken as a means to obtain falling film thickness, and it was observed that measured film thickness was in good agreement with DLAS method and shadowgraph technique, and the deviation between these two techniques was 4.1 % when the falling film was stable.

关键词： Urea

来源：评论

学校读者我要写书评

暂无评论

Analysis of subcooled boiling in PWR rod bundle channel

引用

Yuanzineng Kexue Jishu/Atomic Energy Science and Technology 2015年第9期49卷 1579-1585页

作者： Zhang, Rui Gan, Fu-Jun Zuo, Qiao-Lin Tian, Wen-Xi Su, Guang-Hui Qiu, Sui-Zheng State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an710049 China Shanghai Nuclear Engineering Research & Design Institute Shanghai200233 China

The RPI (Rensselaer Polytechnic Institute) wall boiling model, embedded in the context of two-fluid model of Fluent14.5, was applied to simulate subcooled boiling in core fuel bundle channel with mixing vanes and space grid. The subcooled boiling key parameters including flow field, temperature field and void fraction distribution were obtained. The analysis of the effect of mixing vanes and space grid on flow channel thermal-hydraulic characteristics was conducted. It is shown that the existence of space grid can cause a large pressure drop, and mixing vanes have a great influence on the key parameters of flow field and temperature field. The results of RPI model show a good agreement with Bartolemei experiment data. ©, 2015, Atomic Energy Press. All right reserved.

关键词： flow fields

来源：评论

学校读者我要写书评

暂无评论

Thermal-hydraulic analysis and metal temperature computation for the water wall of a 1000MW ultra supercritical tower boiler with double reheat

Thermal-hydraulic analysis and metal temperature computation...

引用

International Conference on power engineering, ICOPE 2015

作者： Yang, Dong Wang, Long Bi, Yanshuang Xie, Beibei Wang, Gang Yao, Danhua State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University No.28 Xianning West Road Xi'an Shaanxi710049 China Shanghai Boiler Works Ltd. No.250 Huaning Road Minhang District Shanghai200245 China

The ultra supercritical boiler technology with double reheat can significantly increase the efficiency of a Rankine cycle power plant, and reduce fuel consumption for a given output. Recently China is developing 1000MW ultra supercritical boiler with double reheat which is arranged in tower type and the steam parameters are 350bar, 605oC/613oC/613oC. Thermal-hydraulic analysis is the key factors for the design and operation of ultra supercritical boiler with double reheat. According to the boiler structure and furnace-sided heat flux, the water wall of an ultra supercritical tower boiler with double reheat is treated in this paper as a flow network system consisting of series-parallel loops, pressure grids and connecting tubes. Based on the mass, momentum and energy conservations and some supplementary equations, a mathematical model is developed. Pressure drop, mass flux distribution, outlet vapor temperatures and metal temperatures data in the water wall at BMCR (boiler maximum continuous rating), 75% THA (turbine heat acceptance) and 30% THA load are obtained by iteratively solving the mathematical model. The results show that the water wall in the ultra supercritical boiler can operate safely. © 2015 The Japan Society of Mechanical Engineers.

关键词： Pressure drop

来源：评论

学校读者我要写书评

暂无评论

Novel method for simultaneous measurement of film thickness and mass fraction of urea–water solution

引用

Chinese Optics Letters 2014年第12期12卷 133-136页

作者：杨荟楠郭晓龙苏明旭蔡小舒 School of Energy and Power Engineering University of Shanghai for Science and Technology Shanghai Key Laboratory of Multiphase Flow and Heat transfer in Power Engineering University of Shanghai for Science and Technology

Quantitative knowledge of the film thickness and mass fraction of the urea-water solution is very crucial in many practical applications. Film thickness or mass fraction can only be determined individually by conventional measurement techniques. We develop a novel measurement method to measure the film thickness and mass fraction of ure^water solution simultaneously. The absorption coefficients of urea-water solution （5 50 wt%） are measured, a pair of optimized wavelengths is then chosen to achieve high measurement sensitivity. Cross validation is also performed and uncertainties of the technique are smaller than 0.68% for thickness measurements and 1.86% for mass fractions.

关键词： Film thickness Metabolism Thickness measurement Uncertainty analysis Urea Water absorption

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：