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Two-dimensional numerical simulation of hydrodynamic behaviors of drop covered with vapor film

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Science China(Technological Sciences) 2005年第2期48卷 180-190页

作者： DUAN Riqiang, JIANG Shengyao, ZHANG Youjie, JIA Haijun & YANG Xingtuan institute of nuclear and new energy technology, Tsinghua University Advanced Reactor Engineering and Safety, Key Laboratory of MOE of China, Beijing 102201, China institute of nuclear and new energy technology Tsinghua University Beijing China Advanced Reactor Engineering and Safety Key Laboratory of MOE of China Beijing China

The breakup of drop covered with vapor film is numerically simulated. The moving particle semi-implicit method is used to solve the 2-dimensional unsteady Navier-Stokes equations for drop, vapor and ambient fluid. The results show that vapor film suppresses the drop breakup and hence the critical Weber number increases with the increasing thickness of vapor film. The breakup process can be divided into two stages. The drop deformation and breakup mainly occur in the later stage. Three breakup mechanisms are unveiled, which are almost the same as that of drop breakup without vapor film except for the stronger Rayleigh-Taylor instability for drop with vapor film. Our simulation results are comparable with the previous experiments.

关键词： drop breakup, vapor film, numerical simulation, particle method, moving particle semi-implicit method.

Kinetics of recovering germanium from lignite ash with chlorinating roasting methods

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Rare Metals 2008年第3期27卷 238-242页

作者： ZHU Guocai WANG Jingyan CHENG Zhuo ZHAO Yuna institute of nuclear and new energy technology Tsinghua University Beijing 102201 China

A process of recovering Ge by chlorinating masting was put forward. GeCl4 was separated and recovered from lignite ash because of its low boiling point. Kinetic analysis indicates that the chlorinating roasting process fits with the unreacted-core shrinking model and the reaction rate equation corresponds to 1 - 2a/3 - （1 - a）2/3 = kt. The apparent activation energy Ea is calculated to be 22.36 kJ·mol^-1. The diffusion of product layer serves as the rate-controlling step in this process. When the roasting temperature is 250℃, the roasting time is 60 min, the con- centration of hydrochloric acid is 10 mol/L, and the ratio of liquid to solid is 10 （mHCl/ash = 10）, and 90% Ge in lignite ash can be recovered.

关键词： lignite ash germanium chlorinating roasting kinetics

Fundamental study of CO_2 control technologies and policies in China

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Science China(Technological Sciences) 2008年第7期51卷 857-870页

作者： JIN HongGuang1, ZHANG XiLiang2, GAO Lin1, YUE Li2, HE JianKun2 & CAI RuiXian1 1 institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100080, China 2 institute of nuclear and new energy technology, Tsinghua University, Beijing 100084, China institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China institute of nuclear and new energy technology Tsinghua University Beijing China

The technical roadmap and policies for CO2 mitigation suitable for China are a common center of attention in the fields of energy, environment, and management science in the country. Emphasizing interaction between technical research and policy research, this work discovers the potential breakthrough in the integrated field. The technical difficulties of recovering CO2 are pointed out, the mechanism of combining CO2 recovery with energy conversion is investigated, and the basic principle for integrating an environmental-friendly energy system is discussed. Moreover, the formulation of a new energy system that can recover CO2 with very low or even zero energy penalty is proposed, while the assessment methodology and model system for the technical roadmap of CO2 emission control are developed. Finally, a new technical roadmap constructing an energy network suitable for China is proposed, which may provide a new way for the development of sustainable energy and environment technologies.

关键词： CO2 capture and storage technical roadmap energy policy

SYSTEM VALIDATION OF COMPUTERIZED PROCEDURE SYSTEM BASED ON MULTI-LEVEL FLOW MODELING

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SYSTEM VALIDATION OF COMPUTERIZED PROCEDURE SYSTEM BASED ON ...

第十八届国际反应堆结构力学大会

作者： Wei Qin Liangju Zhang institute of nuclear and new energy technology Tsinghua University

＜正＞ Computerized Procedure System （CPS） is a kind of operator assistant system. In this work an approach suggests the application of an MFM model to dynamic system validation of CPS’s procedure files, under the context of a simulation or a real nuclear Power Plant （NPP） condition. It should be possible to determine, using the model, whether CPS is working in a manner that requirements for CPS is going to be achieved, and this validation is based on requirements of CPS to achieve or maintain the NPP system to or in a desired operation state. The modeling procedure of a MFM model is as follows: （1） The top goal of a system is first

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Role of Demonstration of the Sino-Dutch Cooperation Project—A Perspective from Rural energy Development in China

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Role of Demonstration of the Sino-Dutch Cooperation Project...

作者： Gu Shuhua institute of nuclear and new energy technology,Tsinghua University,Beijing 100084

The paper analyzes the experiences that led to the success of the Sino-Dutch Cooperation Project,including technology selection,fund use,project objective setting, organization and management and dissemination *** exp... 详细信息

关键词： rural renewable energy project objective significance of demonstration

Electron irradiation effects on DC electrical performances of SiGe HBT in a comparison with Si BJT

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Rare Metals 2004年第4期23卷 330-339页

作者： MENGXiangti ZHANGXimin WANGJilin HUANGWentiao CHENPeiyi KLAHongyong instituteofnuclearandnewenergytechnology TsinghuaUniversityBeijing100084China instituteofMicroelectronics TsinghuaUniversityBeijing100084China

The DC characteristics of SiGe HBT irradiated at different electron dose havebeen studied in a comparison with those of Si B JT. Generally, I_b and I_b - I_(b0) increase, I_c,I_c -I_(c0) and its +/- transition V_(be) as well as DC current gain ft decreases with increasingdose; increase of I_b -I_(b0) with increasing dose for Si BIT is much larger than that for SiGe HBT;beta increases with V_(be) or I_b, but decreases at I_b < 0.25 mA with I_b, and congregates athigher dose; and a damage factor d(beta) is much less at the same dose for SiGe HBT than for Si *** HBT has much better anti-radiation performance than Si BJT. Some anomalous phenomena forincrease of I_c, I_c -I_(c0), I_b -I_(b0) and beta at low dose have been found. Some electron trapshave been measured. The mechanism of changes of characteristics is discussed.

关键词： semiconductor technology SiGe HBT electron irradiation Si BJT DCelectrical performance

APPLICATION OF DSP IN ACTIVE MAGNETIC BEARING（AMB-F） CONTROL FOR THE HTR-10GT

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APPLICATION OF DSP IN ACTIVE MAGNETIC BEARING（AMB-F） CONTR...

第十八届国际反应堆结构力学大会

作者： Huan Yu Lei Shi Suyuan Yu institute of nuclear and new energy technology Tsinghua University

＜正＞ The HTR-10GT is designed by the institute of nuclear and new energy technology （INET） of Tsinghua University in China to study the 10 MW high temperature gas-cooled test modular reactor coupled with direct gas-turbine cycle. In this project, active magnetic bearing （AMB） is exclusively chosen to support the turbomachine rotors in the power conversion unit because of its numerous advantages over the conventional bearing.

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The Study of Dynamics of Molecular Highly Excited Vibrational States with Dynamical Potential Approaches

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The Study of Dynamics of Molecular Highly Excited Vibrationa...

第十六届全国原子与分子物理学术会议

作者： Fang Chao institute of nuclear and new energy technology,Tsinghua University.Beijing.China,100084

The highly excited vibrational state is hard to study by the quantum mechanical calculation because of its nonlinear *** constructed the algebraic Hamiltonian,dynamical potential and action integral for its *** comprehensive research,we elucidated some essential dynamical characteristics of the highly excited vibrational states of four integrable systems(HCP, DCP,HOCl and HOBr),including their *** important result is the classification of energy levels under the concept of polyad *** these,we also discovered that by the dynamical symmetry we could transfer our conclusions to the other systems yet to be studied. Furthermore,we studied the HCO *** the Lyapunov exponent,we discovered that the vibrational states of HCO with chaotic motion would be more stable,and more intramolecular vibrational relaxation will be involved,*** conclusions are helpful for us to understand the molecular highly excited vibrational dynamics

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DETAIL VIBRATION ANALYSIS OF MAGNETIC BEARING HELIUM FAN IN HIGH TEMPERATURE REACTOR

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DETAIL VIBRATION ANALYSIS OF MAGNETIC BEARING HELIUM FAN IN ...

第十八届国际反应堆结构力学大会

作者： Yang Xu Guojun Yang Lei Zhao institute of nuclear and new energy technology Tsinghua University

＜正＞ 1 INTRODUCTION Since the pure helium environment inside the reactor, Active Magnetic Bearing （AMB） is considered to be the best for the helium fan supported. Using AMB in such an important place, the coming problem must be solved is to know the detail rotor dynamics and vibration issue of it while the rotor length has been increased and the bearing stiffness been decreased. As most of conventional mechanical machine, this issue has to be well studied during the design stage. If the helium fan could run on 10% away from the critical speed, the risk of unexpected vibration will be well avoided, and it can fit for all the requirements as well.

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