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第十届全国动力学与控制学术会议

作者： XUE Yang XIONG Fu-rui SUN Jian-qiao Department of Mechanics Tianjin UniversityTianjin300350China Science and Technology on Reactor System Design Technology LaboratoryNuclear Power Institute of ChinaChengdu 610041China School of EngineeringUniversity of CaliforniaMercedCA 95343USA

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Multi-objective Optimization of Elastic Beams For Minimum Weight and Sound Radiation

Multi-objective Optimization of Elastic Beams For Minimum We...

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第十届全国动力学与控制学术会议

作者： Meng-xin He Fu-Rui Xiong Yousef Naranjani Qian Ding Jian-Qiao Sun Department of Mechanics Tianjin University Tianjin300072China Science and Technology on Reactor System Design Technology LaboratoryNuclear Power Institute of ChinaChengdu 610041China School of EngineeringUniversity of California MercedCA 95343USA

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Natural convective heat transfer from a heated slender vertical tube in a cylindrical tank 16

Natural convective heat transfer from a heated slender verti...

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16th International Topical Meeting on Nuclear reactor Thermal Hydraulics, NURETH 2015

作者： Xian, Lin Jiang, Guangming Yu, Hongxing Science and Technology on Reactor System Design Technology Laboratory Chengdu610041 China Nuclear Power Institute of China Chengdu610041 China

ISBN: (纸本)9781510811843

Natural convective heat transfer in enclosures is widely researched in extensive range of engineering application such as passive residual heat removal system (PRHRS) in nuclear plant, solar collectors and cooling of electronic equipment. After Fukushima incident, the application and researching of PRHRS have been gaining more and more attention. It still has no proper calculating tools to analyze natural convective heat transfer with large L/D ratio and high Rayleigh number in PRHRS. In this paper, based on some former natural convective heat transfer experiments, numerical simulations and scale analysis, the single phase natural convective heat transfer correlation from the vertical tube have been developed. Transient single phase natural convection heat transfer along vertical tube in a cylindrical enclosure has been investigated for water with widely used computational fluid dynamic (CFD) engineering program ANSYS CFX-12. The influence brought by different geometry of tube and mesh scales has been evaluated by the results of former experiments. The ratio of tube length to diameter is a dimensionless factor affects heat transfer rate. The evaluation of thermal stratification to natural convective heat transfer in enclosure has been studied. Numerical simulation covers large L/D and high Rayleigh number natural convection: 108RaL14. Based on the scale analysis of natural convection cylindrical boundary equations the new dimensionless group has been put forward contains L/D factor. The new natural convective heat transfer along the vertical single tube model has been build according to the former experiments1 results. After combining numerical simulation results, the new model covers the higher Rayleigh number range of natural convection.

关键词： Natural convection

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Research on large equipment maintenance system in life cycle

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IOP Conference Series: Earth and Environmental science 2017年第1期69卷

作者： Xiaowei Xu Hongxia Wang Zhenxing Liu Nan Zhang School of Automobile and Traffic Engineering Wuhan University of Science and Technology Wuhan 430081 China Hubei Key Laboratory of Power System Design and Test for Electrical Vehicle Xiangyang 441053 China

In order to change the current disadvantages of traditional large equipment maintenance concept, this article plans to apply the technical method of prognostics and health management to optimize equipment maintenance strategy and develop large equipment maintenance system. Combined with the maintenance procedures of various phases in life cycle, it concluded the formulation methods of maintenance program and implement plans of maintenance work. In the meantime, it takes account into the example of the dredger power system of the Waterway Bureau to establish the auxiliary platform of ship maintenance system in life cycle.

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Large eddy simulation of turbulent flow in the rod bundle with different spacer grids 23

Large eddy simulation of turbulent flow in the rod bundle wi...

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23rd International Conference on Nuclear Engineering: Nuclear Power - Reliable Global Energy, ICONE 2015

作者： Wei, Zonglan Yu, Zhang Liu, Songtao Science and Technology on Reactor System Design Technology Laboratory NPIC Chengdu Sichuan China Nuclear Power Design and Research Sub-Institute NPIC Chengdu Sichuan China

ISBN: (纸本)9784888982566

Large eddy simulation(LES) of the swirling flow in the rod bundle subchannels with spacer grids are presented. According to the rod bundle flow benchmark experiment, the 5×5 rod bundle with a split-type spacer grid is simulated by this transient simulation with a fine hybrid mesh. Mean velocity components, RMS (root mean square) velocity components and turbulent kinetic energy profiles at different locations downstream the mixing vanes are compared between the experiment and simulation results. LES results can reproduce the mixing turbulent flow velocity field well. We also have studied the influence of the mixing vanes' bending degree on the subchannel flow structures by using LES to simulate the 3×3 rod bundle with the typical PWR spacer grid. The mixing vanes' bending degree is modified to 35°and 40°based on the original spacer grid, whose mixing vanes' bending degree is 30°. The larger bending degree produces a stronger mean coolant mixing effect, while larger pressure loss and fluctuation come together with this effect. The increased pressure loss would generate additional flow resistance, and larger fluctuation of coolant flow would make the mixing effect unstable, as well as would cause flow-induced vibration and grid-to-rod fretting phenomena. The LES method is a viable tool to optimize the spacer grid design and provide transient flow field data for mechanical analysis. Copyright © 2015 by JSME.

关键词： Mixing

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Fire compartment partitioning approaches for fire probabilistic safety analysis of a high-temperature gas-cooled reactor 8

Fire compartment partitioning approaches for fire probabilis...

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8th International Topical Meeting on High Temperature reactor technology, HTR 2016

作者： Geng, Yuhao Zhao, Jun Tong, Jiejuan Wang, Wei Di Maio, Francesco Zio, Enrico Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety Ministry of Education Tsinghua University Beijing100084 China Energy Department Politecnico di Milano Via La Masa 34 Milano20156 Italy System Science and the Energetic Challenge Fondation EDF-Electricite de France Ecole Centrale Supelec Paris Chatenay-Malabry Cedex Paris92295 France

ISBN: (纸本)9780894487323

Fire compartment partitioning is the foundational task in Fire Probabilistic Safety Analysis (FPSA), that requires approaches able to balance analytical accuracy and computational burden. In this work, two fire compartment partitioning approaches are illustrated and applied to an electric building of a High-Temperature Gas-Cooled reactor (HTGR, e.g., HTR-PM), and the quantified risks of the compartments obtained with the two approaches are compared. The results show that risk is insensitive to the utilized fire compartment partitioning approach, making the FPSA tasks easier to be performed.

关键词： Fires

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Study On Adaptive Electromagnetic Balancing Ability Improvement By Field Balancing For Motorized Spindle

Study On Adaptive Electromagnetic Balancing Ability Improvem...

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The 29th International Congress on Condition Monitoring and Diagnostic Engineering Management

作者： HW Fan XH Zhang MQ Jing H Liu BJ Shi HW Ma QH Mao School of Mechanical Engineering Xi'an University of Science and Technology Key Laboratory of Education Ministry for Modern Design & Rotor-bearing System School of Mechanical Engineering Xi'an Jiaotong University

Motorized spindle is widely used in the high-speed machine tools,which has the greatly high machining quality and ***,the dynamic performance of high-speed motorized spindle can be reduced by rotor unbalance,because the unbalance-induced vibration is very sensitive for the rotating speed increase of machine tool *** order to correct unbalance in the rotating condition and without human interference,an electromagnetic adaptive balancing system is ***,the electromagnetic balancing device has the limited balancing ability in itself,so it is very necessary to carry out the field balancing to improve the online active balancing *** on the single-plane balancing scheme,a field balancing program was developed and the corresponding balancing test was *** results show the field balancing is effective for the improvement of electromagnetic active balancing *** research work provides a new rotor balancing strategy for the high-speed precision motorized spindle.

关键词： motorized spindle online active balancing electromagnetic balancing device adaptive balancing method balancing ability field balancing

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Balance Compensation Study of Electromagnetic Active Balancer for Motorized Spindle

Balance Compensation Study of Electromagnetic Active Balance...

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2016 13th International Conference on Ubiquitous Robots and Ambient Intelligence (URAI)

作者： Bijia Shi Minqing Jing Hongwei Fan Heng Liu Qian Wang Key Laboratory of Education Ministry for Modern Design & Rotor-bearing System School of Mechanical Engineering Xi'an Jiaotong University School of Mechanical Engineering Xi'an University of Science and Technology

With the increase of rotating speed, the rotor unbalance of the modern rotating machinery becomes more sensitive. The on-line active balance is an ideal balancing mode for precision machines. Electromagnetic balancer is a non-contact new-structure balancing device in the on-line balancing field, as it can reliably work in high-speed condition and keep the position balanceable after turning down. Balance ability is an important indicator evaluating the performance of a balancer. This paper studies a new electromagnetic balancer carrying permanent magnet for the motorized spindle. Because the counterweight disk is the primary moving element of the balancer, its balance compensation value and distribution are mainly discussed in this paper. Based on the existing disk structure, the balance ability of disks with different structure is researched. The two counterweight disks with the same compensation value and distribution angle, the two disks have the same compensation value and different distribution angles, the two disks have different compensation values and the same distribution angle are analysed. The calculation results demonstrate that the first scheme is proven better in the balance ability and can be easily developed.

关键词： Motorized spindle Active balancing Counterweight disk Electromagnetic balancer Balance ability

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Study on Unbalance Magnetic Pull of the Motorized Spindle under Different Rotor Eccentricities

Study on Unbalance Magnetic Pull of the Motorized Spindle un...

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2016 13th International Conference on Ubiquitous Robots and Ambient Intelligence (URAI)

作者： Jin Wang Minqing Jing Hongwei Fan Heng Liu Bijia Shi Key Laboratory of Education Ministry for Modern Design & Rotor-bearing System School of Mechanical Engineering Xi'an Jiaotong University School of Mechanical Engineering Xi'an University of Science and Technology

High-speed precision machining is one of the important development directions of modern machining technology, high-speed spindle system is widely used in high-speed machining, and motorized spindle is the main choice of the high-speed machine tool spindle. The electromagnetic force caused by rotor unbalance is one of main vibration sources of motorized spindle. Firstly, the research on the frequency spectrum characteristic of electromagnetic force under different rotor eccentricities is very necessary to suppress electromagnetic vibration. An electromagnetic finite element model was built for a motorized spindle based on Ansoft Maxwell in this paper. The electromagnetic force spectrum variation under the static and dynamic eccentricities is studied. The Unbalance Magnetic Pull(UMP) of the motorized spindle under different rotating speeds and different eccentricities are analysed. The results show that the motorized spindle with the static or dynamic eccentricity both produces new components in the electromagnetic force. Simultaneously, the eccentricity increase positively results in the increase of UMP amplitude. The UMP is constant under the rotor static eccentricity, which has a small impact on rotor vibration, while the frequency of UMP under the rotor dynamic eccentricity is the rotating frequency, which will increase the motorized spindle vibration. Finally, by the experiment the correctness of theoretical analysis and simulation are verified. This work provides a theoretical foundation for the fault diagnosis and dynamic balance of the motorized spindle.

关键词： Machine tool motorized spindle Unbalance Magnetic Pull(UMP) Rotor eccentricity Finite element analysis Frequency spectrum analysis

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Application of STPA to the digital reactor protection system in NPP for system safety analysis 23

Application of STPA to the digital reactor protection system...

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23rd International Conference on Nuclear Engineering: Nuclear Power - Reliable Global Energy, ICONE 2015

作者： Liu, Zhaohui Wu, Zhiqiang Yang, Xiaohua School of Computer Science and Technology University of South China Hengyang421001 China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China Chengdu610041 China

ISBN: (纸本)9784888982566

In NPP, the digital control system which integrated software and hardware are increasingly used to improve dependability and introduce new functionality. Traditional safety analysis can get a good result when handling accidents caused by component failures, but software does not fail in this way. STPA is a new hazard analysis technique based on systems theory rather than reliability theory. It considers the system as a whole (include the hardware and software) to analyze failure and causality of systems and treats safety as a control problem rather than a failure problem. Being a safety-critical system, RPS in NPP needs to be considered carefully in system safety. So, we adopt this new approach to analyze the design process. From the analysis results, we found that causal factors leading to safety accidents identified by STPA included all the hazards identified by the fault tree analysis. Furthermore, there are some causal factors that were identified by STPA only. We utilize these results of the analysis on causation factor to refine the safety requirements and reduce the occurrences of the hazardous scenarios. Copyright © 2015 by JSME.

关键词： Fault tree analysis

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