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Torque model of hydro turbine with inner energy loss characteristics

Science China(Technological Sciences) 2010年第10期53卷 2826-2832页

作者： ZENG Yun1,2, GUO YaKun2, ZHANG LiXiang1, XU TianMao3 & DONG HongKui4 1 Construction engineering College, Kunming university of Science and Technology, Kunming 650051, China 2.school of engineering, university of aberdeen, aberdeen ab2. 3ue, uk 3 Computing Center, Kunming university of Science and Technology, Kunming 650051, China 4 Hydraulic Energy Department, Yunnan Electric Power Test and Research Institute, Kunming 650217, China Construction engineering College Kunming University of Science and Technology school of engineering University of Aberdeen

This paper presents the result and analysis of the composition of energy loss occurring in the hydro turbine. Two new types of energy losses,namely the hydraulic loss in the flow channel and the impact loss,are defined. All losses within the hydro turbine are divided into four types and the loss coefficients are defined accordingly. Expressions or characteristic descriptions of these losses as well as the calibration method of the loss coefficients are presented. Furthermore,the torque model of the hydro turbine where the inner energy loss takes place is established. The developed model has been used to calculate the power loss due to the mechanical friction generated by the units’ rotation to solve the difficulty of measurements of the mechanical friction loss in the hydro turbine. The definition of the impact loss explains the phenomenon that the loss of no-load is greater than that of the rated operation. A set of conversion coefficients are defined using the characteristic parameters at the rated operation,which are used to transform the parameters in the torque model into those that are easily measured. Therefore,the expression of the hydro turbine power is converted into a function that has the main servomotor displacement as its single variable. This makes the proposed model be convenient to use. Finally,the proposed model and methods are calibrated and verified using the measured data of a hydropower plant. Good agreement between the modeled results and the measurements indicates that the proposed model can represent the inner energy loss characteristics of the hydro turbine.

关键词： hydraulic loss in flow channel impact loss loss coefficients conversion coefficients

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SOME NEW DATA AND FORMULAS FOR RESISTANCE FLOW IN FLUVIAL OPEN CHANNELS

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Journal of Hydrodynamics 2011年第4期23卷 527-534页

作者： YANG Sheng-fa HU Jiang LI Dan-xun WANG Xing-kui GUO Yakun Department of River and Ocean Chongqing Jiaotong University Chongqing 400074 China State Key Laboratory of Hydroscience and engineering Tsinghua University Beijing 100084 China school of engineering University of Aberdeen Aberdeen AB24 3UE UK

Flow resistance in fluvial open channels, especially in steep gravel-bed channels, still presents challenges to researchers and engineers. This article presents some new data from both the flume experiments and field measurements. Data analysis using the divided hydraulic radius approach shows that the relative roughness plays a significant role in the bed form resistance. A new set of formulas that incorporate the relative roughness are proposed. As compared with several existing formulas, the proposed formulas can be used to better estimate the bed form resistance.

关键词： open channel flow flow resistance relative roughness steep gravel-bed flume experiments field measurements

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Synthesis and Characterization of a Novel Gallophosphate with Ethylene Glycol

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Chemical Research in Chinese Universities 1995年第4期11卷 357-359页

作者： KAN Qiu-bin and XU Ru-ren(Department of Chemistry,Jiliu university,Changchun,130023)Glasser,F.P. (Dept.of Chem.,university of aberdeen,Meston Walk, Old aberdeen ab9 2ue,U,K.) JILIN UNIV DEPT CHEMCHANGCHUN 130023PEOPLES R CHINA UNIV aberdeen DEPT CHEMOLD ABERDEEN AB9 2UESCOTLAND

ＳｙｎｔｈｅｓｉｓａｎｄＣｈａｒａｃｔｅｒｉｚａｔｉｏｎｏｆａＮｏｖｅｌＧａｌｌｏｐｈｏｓｐｈａｔｅｗｉｔｈＥｔｈｙｌｅｎｅＧｌｙｃｏｌＫＡＮＱｉｕ－ｂｉｎａｎｄＸＵＲｕ－ｒｅｎ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓ... 详细信息

ＳｙｎｔｈｅｓｉｓａｎｄＣｈａｒａｃｔｅｒｉｚａｔｉｏｎｏｆａＮｏｖｅｌＧａｌｌｏｐｈｏｓｐｈａｔｅｗｉｔｈＥｔｈｙｌｅｎｅＧｌｙｃｏｌＫＡＮＱｉｕ－ｂｉｎａｎｄＸＵＲｕ－ｒｅｎ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＪｉｌｉｕＵｎｉｖｅｒｓｉ...

关键词： Gallophosphate Ethylene glycol Synthesis

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灵光独耀:沈宗灵与中国法理学

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中国法律评论 2024年第4期 149-154页

作者： Peking university Law school 北京大学法学院

在其诸多弟子的追忆中,沈宗灵先生一生专心治学、淡泊名利,由此常常对世事保持一种有意的疏离。“灵光独耀,迥脱根尘”,或许便是这位法理学大家的灵魂写照。壹“经国济民”:沈宗灵的早年岁月1923年2月24日,沈宗灵出生于浙江杭州的一个... 详细信息

在其诸多弟子的追忆中,沈宗灵先生一生专心治学、淡泊名利,由此常常对世事保持一种有意的疏离。“灵光独耀,迥脱根尘”,或许便是这位法理学大家的灵魂写照。壹“经国济民”:沈宗灵的早年岁月1923年2月24日,沈宗灵出生于浙江杭州的一个商人家庭,后随家人迁居上海。

关键词：沈宗灵淡泊名利法理学浙江杭州灵光

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Entropy Assessment on Environmental Influence of Condense Heat in Recovery System in Air-Conditioning Refrigerating Machine

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湖南大学学报（自然科学版） 2009年第S1期36卷 96-101页

作者： TANG Wen-wu1,2,WANG Han-qing1,2(1.school of Energy Science and engineering,Central South university,Changsha,Hunan 410083,China 2.school of Civil engineering,Hunan university of Technology,Zhuzhou,Hunan 412008,China) school of Energy Science and engineering Central South University Changsha 410083 China school of Civil engineering Hunan University of Technology Zhuzhou 412008 China

This paper presented an entropy evaluation method for the influences of condense heat recovery system on the *** at the damage of the condense heat to the environment,an entropy of resource loss and an emission entropy from the condense heat recovery system in the air conditioning refrigerating machine were *** the evaluation of the entropies,we developed a new algorithm for the parameter identification,called the composite influence coefficient,based on the Least Squares Support Vector Machine *** simulation,the numerical experiments shows that the Least Squares Support Vector Machine method is one of the powerful methods for the parameter identification to compute the damage entropy of the condense heat,with the largest training error being-0.025(the relative error being-3.56%),and the biggest test error being 0.015(the relative error being 2.5%).

关键词： air-conditioning refrigerating machine condense heat entropy evaluation LS-SVM

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Chinese expert consensus on the clinical application of drugcoated balloon(2^(nd) Edition)

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Journal of Geriatric Cardiology 2024年第2期21卷 135-152页

作者： The Expert Writing Committee of the Chinese Expert Consensus on Clinical Applications of Drug-Coated Balloon(2^(nd)Edition) Jun-Bo GE Yun-Dai CHEN 不详 Zhongshan Hospital Fudan University Chinese PLA General Hospital

Percutaneous coronary interventions have progressed through the era of plain balloon dilation, bare-metal stent insertion to drug-eluting stent treatment, which has significantly reduced the acute occlusion and restenosis rates of target vessels and improved patient prognosis, making drug-eluting stents the mainstream interventional treatment for coronary artery disease. In recent years, drug-coated balloons(DCBs) have become a new treatment strategy for coronary artery disease, and the drugs used in the coating and the coating technology have progressed in the past years. Without permanent implant, a DCB delivers antiproliferative drugs rapidly and uniformly into the vessel wall via the excipient during a single balloon dilation. Many evidence suggests that DCB angioplasty is an effective measure for dealing with in-stent restenosis and de novo lesions in small coronary *** more clinical studies are published, new evidence is emerging for the use of DCB angioplasty in a wide range of coronary diseases, and the indications are expanding internationally. Based on the latest research from China and elsewhere, the Expert Writing Committee of the Chinese Expert Consensus on Clinical Applications of Drug-Coated Balloon has updated the previous DCB consensus after evidence-based discussions and meetings in terms of adequate preparation of in-stent restenosis lesions, expansion of the indications for coronary de novo lesions, and precise guidance of DCB treatment by intravascular imaging and functional evaluation.

关键词： balloon drugs dealing

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External synchronization of two dynamical systems with uncertain parameters

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Science China(Technological Sciences) 2010年第3期53卷 731-740页

作者： HAN QingKai 1,SUN XiaoYu 2,YANG XiaoGuang 3 &WEN BangChun 1 1 school of Mechanical engineering&Automation,Northeastern university,Shenyang 110004,China 2.school of Electrical engineering,Shenyang university of Technology,Shenyang 110023,China 3school of Mechanical engineering,The university of Birmingham,Birmingham,B15 2TT,uk school of Mechanical engineering & Automation Northeastern University school of Electrical engineering Shenyang University of Technology school of Mechanical engineering The University of Birmingham

External synchronization is addressed as two or more dynamical systems with synchronous motions,which is also regarded as master-slave *** this paper,two dynamical systems,one employs a hysteretic term to model the friction phenomenon,the other involves a hardening stiffness component with the third order of displacement due to flexible deformation,are controlled to converge to the same *** control strategy is extended from feedback control for all parameters known to adaptive control for linear parameters unknown and all parameters *** slave system can keep synchronous motions with the movements of master via the designed control strategy even all the parameters are not *** stability of synchronization error,the transient process into synchronization and the effects of parameters on the designed controller using different control strategies are *** simulation results unfold the feasibility and effectiveness of this synchronization method.

关键词： controlled synchronization uncertain parameters hysteretic system Duffing system

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Progress of Lyman-alpha-based beam emission spectroscopy(Ly BES)diagnostic on the HL-2A tokamak

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Plasma Science and Technology 2024年第3期26卷 118-125页

作者：周艺轩余羿许敏柯锐聂林徐皓赵光义刘灏袁子豪肖晨雨李继全肖池阶 the HL-2A Team Southwestern Institute of Physics Chengdu 610041People's Republic of China Sino-French Institute of Nuclear engineering and Technology Sun Yat-sen UniversityZhuhai 519082People's Republic of China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China

An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2A *** 20-channel edge LyBES,which is intended to measure the density fluctuation in plasma edge(from R=1960 mm to R=2026 mm)with an improved spatial resolution of 3.3 mm,is a complement to the existing conventional beam emission spectroscopy(BES)*** this article,we introduce the progress of LyBES diagnostic,including the collection optics,the monochromator,and the detector *** reflectance of the collection mirrors is measured to be~82%at 122 nm,and the aberration geometrical radius of the collection optics is tested to be~150μm in the aimed *** linear dispersion of the LyBES monochromator is designed to be~0.09 nm mm^(-1).The bandwidth of the detector system with the 5×10^(7)V A^(-1)preamplifier gain is measured to be~280 kHz,and the peak-to-peak noise of the detector system is tested to be~16 *** finalized design,components development and testing of the LyBES diagnostic have been completed at present,and an overall performance of the LyBES diagnostic is to be confirmed in the next HL-2A campaign.

关键词： density fluctuation Ly BES BES vacuum ultraviolet

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An adaptive scaled boundary finite element method by subdividing subdomains for elastodynamic problems

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Science China(Technological Sciences) 2011年第S1期54卷 101-110页

作者： ZHANG ZiHua 1,2,YANG ZhenJun 2,LIU GuoHua 1 & HU YunJin 1 1 College of Civil engineering and Architecture,Zhejiang university,Hangzhou 310058,China 2.school of engineering,university of Liverpool,L69 3GQ,uk College of Civil engineering and Architecture Zhejiang University school of engineering University of Liverpool

The scaled boundary finite element method(SBFEM) is a semi-analytical numerical method,which models an analysis domain by a small number of large-sized subdomains and discretises subdomain boundaries *** a subdomain,all fields of state variables including displacement,stress,velocity and acceleration are semi-analytical,and the kinetic energy,strain energy and energy error are all integrated *** advantages are taken in this study to develop a posteriori h-hierarchical adaptive SBFEM for transient elastodynamic problems using a mesh refinement procedure which subdivides *** only a small number of subdomains are subdivided,mesh refinement is very simple and efficient,and mesh mapping to transfer state variables from an old mesh to a new one is also very simple but *** 2D examples with stress wave propagation were *** results show that the developed method is capable of capturing propagation of steep stress regions and calculating accurate dynamic responses,using only a fraction of degrees of freedom required by adaptive finite element method.

关键词： scaled boundary finite element method subdivision of subdomains h-hierarchical adaptivity mesh mapping transient elastodynamics

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Analysis of Micro Thermal Environment for Residential District Planning

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湖南大学学报（自然科学版） 2009年第S1期36卷 51-54页

作者： ZHANG Wei-jie1,QI Jing2,JIN Wen2(1.Institute of Urban Construction,Hebei university of engineering,Handan,Hebei 056038,China 2.school of Architecture,Hebei university of engineering,Handan,Hebei 056038,China) Institute of Urban Construction Hebei University of Engineering Handan 056038 China school of Architecture Hebei University of Engineering Handan 056038 China

This paper focused on residential district planning *** GIS and SketchUp software,a common digital relief map model of a residential district was created,and the air distribution(both velocity and temperature)within this residential district was established by CFD ***,the velocity and temperature of the air at any location within the residential district,as well as the worse flow area and overheat area can be clearly *** index of micro thermal environment for the air distribution evaluation was *** on a certain residential district planning model,from the air parameters of the micro environment at any location within the residential district,such as air velocity and air temperature,the index of micro thermal environment was obtained by certain principles and data processing *** this index,the residential district planning scheme was evaluated corresponding to the thermal characteristics of the residential *** this index is not good enough or unsatisfied,the residential district planning idea and process can be changed or improved accordingly in order to get a better thermal characteristics of the residential district judged by the established evaluation index system.

关键词： residential district planning micro thermal environment micro thermal environmental index CFD SketchUp

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