检索结果-内蒙古大学图书馆

ASME 2000 International Mechanical engineering Congress and Exposition, IMECE 2000

作者： Guo, Lie-Jin Feng, Zi-Ping Xi'an Jiaotong University State Key Laboratory of Multiphase Flow in Power Engineering Shaanxi Province Xi'an710049 China

ISBN: (纸本)9780791826621

In the present paper the experiments for subcooled water flow and steam-water two-phase flow were conducted to investigate the effects of pulsation upon transient heat transfer characteristics in a closed-circulation helical-coiled tube steam generator. The non-uniform property of local heat transfer with steady flow was also examined. The secondary flow mechanism and the effect of interaction between the flow oscillation and secondary flow were analyzed cm the basis of the experimental data. Some new phenomena were observed and explained. A series of correlations were proposed for the average and local heat transfer coefficients both under steady and oscillatory flow conditions. The results showed that there were considerable variations in local and peripherally time-averaged Nusselt numbers for pulsating flow in a wide range of parameters. Systematic investigations of pressure drop type oscillations and their thresholds for steam-water two-phase flow in a uniformly heated helical tube were also reported. Copyright © 2000 by ASME

关键词： Drops

来源：评论

学校读者我要写书评

暂无评论

Improvement and experimental study of scroll expander for organic rankine cycle

引用

Energy engineering: Journal of the Association of Energy engineering 2020年第4期117卷 225-235页

作者： Li, Lei Tao, Leren Gou, Yanan Zhang, Shan Zaozhuang University Zaozhuang277160 China University of Shanghai for Science and Technology Shanghai200093 China Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering Shanghai200093 China

The scroll expander used in organic Rankine cycle (ORC) system is improved, and its performance is analyzed experimentally. The modified profile and inlet hole of the scroll expander are enhanced, and the performance of the scroll expander before and after the improvement is analyzed. The results show that when the inlet pressure exceeds 0.7 MPa, the waist-shaped hole with a larger area is preferable. The scroll expander with a waist-shaped hole has a larger output power and wider optimal pressure range, and when the inlet pressure is 1.6 MPa, the maximum output power increases by 230 W. The output power and isentropic efficiency of the scroll expander can be improved by modifying the profile. When the inlet pressure is 1.6 MPa and the rotational speed is 1750 r/min, the maximum output power of the scroll expander is 1235 W, which is 120 W higher than that before the improvement. © 2020, Tech Science Press. All rights reserved.

关键词： Rankine cycle

来源：评论

学校读者我要写书评

暂无评论

Experimental Investigation on flow Pattern and Bubble Behavior during Subcooled flow Boiling of R1233zd(E)in Parallel Channels

引用

Journal of Thermal Science 2023年第6期32卷 2374-2385页

作者： FANG Yidong ZHANG Zhao XU Dan WANG Yuchen YANG Huinan HUANG Yuqi School of Energy and Power Engineering University of Shanghai for Science and TechnologyShanghai200093China Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering Shanghai200093China Key Laboratory of Clean Energy and Carbon Neutrality of Zhejiang Province Jiaxing Research InstituteZhejiang UniversityJiaxing314031China Key Laboratory of Smart Thermal Management Science&Technology for Vehicles of Zhejiang Province Taizhou317200China

In this study,the flow pattern and bubble behavior of R1233zd(E)during subcooled flow boiling in parallel channels are experimentally investigated with visualization and thermal *** test section is composed of 21 rectangular mini channels with the hydraulic diameter of 1.5 mm and the length of 140 *** flow,slug flow,churn flow and wavy-annular flow occur in sequence with the increase of vapor quality,while transient flow pattern transition process involving multiple flow patterns are also *** distribution of flow pattern is non-synchronized and axial-asymmetric,with earlier flow pattern transitions observed in peripheral channels away from the center *** initial nucleate site in each channel also show a random and axial-asymmetric distribution,while faster bubble growth can be noted in some channel under the comprehensive effects of liquid evaporation and bubble *** variation of heat transfer coefficient is correspondence to the flow pattern transition,showing different trends along the flow *** increase of mass flux can lead to delayed flow pattern transition and variation of heat transfer *** addition,higher heat transfer coefficient can be noted in channels away from the center axis.

关键词： flow boiling flow pattern bubble behavior parallel channel visualization

来源：评论

学校读者我要写书评

暂无评论

Multi-objective optimization research of open and closed air brayton cycle

引用

International Journal of Advanced Nuclear Reactor Design and Technology 2024年第1期6卷 21-31页

作者： Song, Meihui Qian, Yiran Leng, Yuyang Liu, Tao Yu, Lianyun Chen, Weixiong State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Shaanxi Xi'an710049 China Reactor Engineering Technology Research Institute China Institute of Atomic Energy Beijing102413 China

Air Brayton cycle obtains the significant advantages of high efficiency, compact structure, easy medium requirement and so on, which is one of the most suitable choices for the mobile nuclear power conversion system. In this paper, system-component combined design method is used to establish the open and closed air Brayton cycle of diverse configurations. Based on performance and compactness targets, the multi-objective optimization is carried out to find the optimal design by nondominated sorting genetic algorithm II and entropy weight method. According to the analysis, the closed intercooling reheating recuperating cycle is the configuration with the best comprehensive performance, with cycle efficiency of 33.58 %, power density of 175.39 kW m−3 and power mass ratio of 68.60 kW t−1. The open simple recuperating cycle is the configuration with the smallest volume and mass, with cycle efficiency of 20.01 %, system volume of 6.56 m3 and system mass of 19.98 t. The closed intercooling recuperating cycle is the most balanced configuration, with cycle efficiency of 31.33 %, volume of 9.06 m3 and system mass of 24.97 t. Based on the optimal results, off-design performance analysis of different environmental conditions is also carried out for the configurations above. © 2024 Xi'an Jiaotong University

关键词： Brayton cycle

来源：评论

学校读者我要写书评

暂无评论

Comparison of hydrogen generation rate between cora-13 test and MELCOR simulation: Clad solid-phase oxidation models using self-developed code MYCOAC

引用

Nuclear Technology 2015年第1期192卷 25-34页

作者： Wang, Jun Corradini, Michael L. Haskin, Troy Zhang, Yapei Lu, Qing Tian, Wenxi Su, Guanghui Qiu, Suizheng Xi'an Jiaotong University State Key Laboratory of Multiphase Flow in Power Engineering Xi'an710049 China University of Wisconsin-Madison College of Engineering MadisonWI53706 United States Nuclear Power Institute of China Chengdu610041 China

To better understand the MELCOR oxidation and degradation models, past work compared the MELCOR model to a CORA experiment (CORA Test 13). These MELCOR analyses specifically focused on fuel bundle heatup and clad oxidation when compared to CORA test data. The comparison allowed the authors to investigate differences between hydrogen generation data and simulation results. Several potential reasons were considered for hydrogen generation rate differences, including MELCOR input power, heat transfer modeling, the clad solid-phase oxidation model, and the gaseous steam diffusion model. This work focuses on the possible uncertainty in the clad oxidation models used in MELCOR. First, the MELCOR nodalization approach for the CORA test was reviewed. Then, the temperature history and spatial variation were examined. One main focus was to consider other clad solid-phase oxidation models to compare the MELCOR models. This was accomplished by developing a separate model, MYCOAC, using MELCOR temperature predictions as input. Finally, the mass transfer resistance of steam diffusion to the clad surface was examined and found to be a small effect. While the Baker-Just solid-phase oxidation model showed better agreement with CORA data at low temperatures, the conclusion in this paper is that the oxidation models are not the major source of uncertainty in hydrogen generation rate differences. Future work will focus on heat transfer modeling of the CORA test.

关键词： Diffusion

来源：评论

学校读者我要写书评

暂无评论

A new model of selective photothermolysis to aid laser treatment of port wine stains

引用

Chinese Science Bulletin 2013年第3期58卷 416-426页

作者： LI Dong HE YaLing WANG GuoXiang WANG YongXian YING ZhaoXia State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Department of Mechanical Engineering The University of AkronAkron 44325-3903USA Department of Dermatology Medical School of Xi'an Jiaotong University

Pulsed dye lasers equipped with cryogen spray cooling(CSC) are now widely used to treat vascular malformation such as port wine stains(PWSs).This paper presents a new integrated model that can quantitatively simulate the cooling of the skin and the heating of the targeted blood vessels in PWSs during laser *** new model is based on the classical homogeneous multi-layer skin model that treats PWS-containing dermis as a mixture of dermal tissue and homogeneously distributed *** propagation in skin and PWSs is simulated by a Monte-Carlo method,which provides accurate description of the light scattering and absorption in the *** response of a targeted vessel in the new model is then obtained from the thermal analysis of a Krogh-unit that consists of the vessel and the surrounding dermal tissues and is buried in *** results from the multi-layer skin model provide appropriate laser influence input as well as the initial thermal condition for the micro-model of the Krogh-unit.A general dynamic relation is also introduced on the surface of skin to quantify the convective cooling of *** model is then applied to dye-laser treatment(wavelength of 585 nm) of PWSs with *** results demonstrate that the present model is able to quantify thermal response of a deeply buried blood vessel in PWSs as a discrete blood vessel does,with a more realistically estimate of the sheltering effect of the dermal tissue(scattering) and blood vessels(absorption) in front of the targeted *** understand the poor response of PWSs in clinic,the thermal characteristics of a targeted vessel was simulated under various *** effects of two morphological parameters,the vessel diameter and the burying depth of the vessel,are then systematically investigated under various pulse durations and fluences of laser.A threshold fluence for given vessel diameter and depth is then estimated quantitatively under the condition of the optimal laser pulse durat

关键词：激光治疗仪 Monte-Carlo方法鲜红斑痣脉冲持续时间激光能量密度热作用皮肤组织集成模型

来源：评论

学校读者我要写书评

暂无评论

Effect of local erosion on flow pattern and particle self-rotation in a cyclone separator

引用

Advanced Powder Technology 2025年第7期36卷

作者： Jianbo Zhao Xiuxun Hao Xiaohan Guo Fei Gao Junling Fan Pan Zhang Guanghui Chen College of Electromechanical Engineering Qingdao University of Science and Technology Qingdao 266061 China College of Chemical Engineering and Key Laboratory of Multiphase Flow Reaction and Separation Engineering of Shandong Province Qingdao University of Science and Technology Qingdao 266042 China

Erosion is an inevitable problem of cyclone separator, and serious erosion will greatly affect the movement of the particles. To improve the understanding of the particle self-rotation in cyclone separator, in this research, we explored the influence of local wall erosion on local vortices and particle self-rotation in cyclone separators, leveraging coupled CFD and DEM simulations. The numerical results show that as erosion thickness grows in the cylinder, particle self-rotation decreases. Particles are prone to aggregation within the cone, which significantly affects their self-rotation speed. When the erosion thickness is only 2 mm or 5 mm, the slight deformation of the wall surface helps break up particle agglomeration, thereby increasing the particle self-rotation speed. However, when the erosion thickness reaches 10 mm or 15 mm, severe wear and deformation create deeper grooves, which promote particle aggregation (the particle self-rotation speed decreases by 7.2 % and 19.9 % respectively, compared to the cyclone separator without wear). Meanwhile, the larger erosion thickness spawns local vortices that alter particle motion trajectory and make them more likely to be captured by internal quasi-forced vortex.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Accelerated methane storage in clathrate hydrates using surfactantstabilized suspension with graphite nanoparticles

引用

Chinese Journal of Chemical engineering 2020年第4期28卷 1112-1119页

作者： Liang Yang Xin Wang Daoping Liu Guomin Cui Binlin Dou Juan Wang Shuqing Hao Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering School of Energy and Power EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China School of Environmental and Chemical Engineering Shanghai University of Electric PowerShanghai 200090China National Engineering Research Center of Coal Preparation and Purification China University of Mining&TechnologyXuzhou 221116China

In this study,enhanced kinetics of methane hydrate formation in the sodium dodecyl sulfate(SDS)solution with different concentrations of suspended graphite nanoparticles(GNPs)were investigated at 6.1-9.0 MPa and 274.15 *** GNPs with rough surfaces and excellent thermal conductivity not only provided a considerable number of microsites for hydrate nucleation but also facilitated the fast hydrate heat transfer in the suspension *** a relatively low pressure of 6.1 MPa,the suspension with 0.4 wt%of GNPs exhibited the minimum induction time of 22 min and maximum methane uptake of 126.1 cm3·***,the methane storage performances of the suspensions with higher and lower concentrations of GNPs were not *** the applied pressure,the temperature increase arising from the hydrate heat in the suspension system with the optimized concentration(0.4 wt%)of GNPs was more significant than that in the traditional SDS ***,compared with those of the system without GNPs,enhanced hydration rate and storage capacity were achieved in the suspensions with GNPs,and the storage capacities were increased by 3.9%-17.0%.The promotion effect of GNPs on gas hydrate formation at low pressure is much more obvious than that at high pressure.

关键词： methane storage clathrate hydrates formation kinetics suspension graphite nanoparticles

来源：评论

学校读者我要写书评

暂无评论

Development of a filtered drag model considering effect of the solid shear rate

引用

Particuology 2022年第12期71卷 63-74页

作者： Lingxue Wang Ming Jiang Qiang Zhou School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'an710049China Engineering Research Center of New Energy System Engineering and Equipment University of Shaanxi ProvinceXi'an710049China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an710049China

This study investigates a 2D gas-solid fast fluidized bed of typical Geldart A particles using highly resolved simulations with two-fluid *** results show that the solid shear rate has a considerable impact on the orientation of the meso-scale structures and hence on the filtered drag *** the basis of the correlation for the filtered drag force established in the literature using the traditional markers(such as filtered solid volume fraction,filtered slip velocity and filter scale),a correction correlated with the solid shear rate in the direction of gravity is proposed for better prediction of the filtered drag *** corrected model is shown to produce improved results in posterior tests of flows in different fluidization regimes including bubbling,turbulent and fast fluidization.

关键词： Gas-solid flows Fluidization Two-fluid model Dimensionless solid shear rate Filtered drag force

来源：评论

学校读者我要写书评

暂无评论

Nanoparticle-induced drag reduction for polyacrylamide in turbulent flow with high Reynolds numbers

引用

Chinese Journal of Chemical engineering 2023年第4期56卷 290-298页

作者： Xiaoping Li Jiaxin Pan Jinwen Shi Yanlin Chai Songwei Hu Qiaorong Han Yanming Zhang Xianwen Li Dengwei Jing State Key Laboratory of Multiphase Flow in Power Engineering&International Research Center for Renewable Energy Xi'an Jiaotong UniversityXi'an 710049China Oil and Gas Technology Research Institute of Petrochina Changqing Oilfield Company Xi'an 710018China

Although having been increasingly studied, there is still controversy as to when the addition of nanoparticles could improve the drag reduction performance of polymer drag reducer and particularly what is the underlying mechanism from the fluid dynamics viewpoint. The drag reduction effects of adding SiO_(2) nanoparticles to various polymer polyacrylamide(PAM) solutions were examined in this *** optimal combination of SiO_(2) nanoparticles with cationic polyacrylamide was ***,the addition of SiO_(2) nanoparticles to cationic polyacrylamide solution was shown to be quite efficient for reducing drag, but only at higher flow rates with Reynolds numbers more than 6000, below which the nanoparticle addition is even negative. The addition of SiO_(2) nanoparticles to the PAM solution is supposed to play a dual role. The first is an increase in flow resistance caused by the Brownian motion of nanoparticles, while the second is a decrease in flow resistance caused by acting as nodes to protect the polymer chain from shear-induced breaking under high shear action. At optimal nanoparticle concentration and under higher Reynolds numbers, the later effect is dominant, which could improve the drag reduction performance of polymer drag reducers. Our work should serve as a guide for the application of natural gas fracturing, where the flow rate is frequently very high.

关键词： Drag reduction SiO_(2)nanoparticle Cationic polymer Brownian motion

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：