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水平轴潮流能发电机组独立变桨距系统

浙江大学学报（工学版） 2013年第3期47卷 528-534页

作者：徐全坤李伟刘宏伟林勇刚石茂顺浙江大学流体传动及控制国家重点实验室浙江杭州310027

针对水平轴潮流能发电机组轮毂空间小、变桨角度大、变桨力矩大等特点,设计一种新型的基于电液比例控制的齿轮齿条传动方案的独立变桨距系统.该系统机械结构紧凑,占用空间小,各个桨叶变桨执行机构相互独立.在分析变桨距载荷的基础上,建... 详细信息

针对水平轴潮流能发电机组轮毂空间小、变桨角度大、变桨力矩大等特点,设计一种新型的基于电液比例控制的齿轮齿条传动方案的独立变桨距系统.该系统机械结构紧凑,占用空间小,各个桨叶变桨执行机构相互独立.在分析变桨距载荷的基础上,建立系统的数学模型,并在AMESim软件中对系统进行了仿真研究.仿真结果表明:该系统顺桨变桨180°只需1.1s,逆桨变桨180°只需3.4s,响应速度快,稳定性好,并且可以实现独立变桨,满足了水平轴潮流能发电机组的变桨要求.

关键词：潮流能发电水平轴独立变桨距液压控制

STUDY ON SPEED-SENSORLESS VECTOR control TRANSDUCER BASED ON DSP

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STUDY ON SPEED-SENSORLESS VECTOR CONTROL TRANSDUCER BASED ON...

2.06年中国机械工程学会年会暨中国工程院机械与运载工...

作者： XU Ming*, JIN Bo*, NING Desheng*, WU Ming, LI Wei* *The state key {2. of {2. power transmission and control, Zhejiang University, hangzhou 31002., china Ningbo Hopea Technique of Industry control Co. Ltd, Ningbo 315153, china

In order to improve reliability and adaptability of control system for induction motors, a speed-sensorless vector control transducer based on DSP is presented. The principle of speed-sensorless vecto

关键词： Speed-sensorless induction motor DSP vector control SVPWM.

Numerical Simulation of Transient 3-D Turbulent Hested Jet into Crossflow in a Thick-Wall T-Junction Pipe

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Journal of Thermal Science 2001年第1期10卷 46-51页

作者： Wu Hailing, Chen Tingkuan, Luo Yushan, Wang Haijun (state key {2. of Multiphase Flow in {2. Engineering,Xi’an Jiaotong University, Xi’an 710049, china) state key {2. of Multiphase Flow in {2. Engineering Xi’an Jiaotong University Xi’an China

The present work is to investigate the transient three-dimensional heated turbulent jet into crossflow in a thickwall T-junction pipe using CFD package. Two cases with the jet-to-crossflow velocity ratio of 0.05 and 0.5 are computed, with a finite-volume method utilizing κ-ε model. Comparison of the steady-state computations with measured data shows good qualitative agreement. Transient process of injection is simulated to examine the thermal shock on the T-junction component. Temporal temperature of the component is acquired by thermal coupling with the fluid. Via analysis of the flow and thermal characteristics, factors causing the thermal shock are studied. Optimal flow rates are discussed to reduce the thermal shock.

关键词： numerical simulation low jet-to-crossflow velocity ratio thick-wall T-junction pipe thermal shock

Numerical simulation of predicting and reducing solid particle erosion of solid-liquid two-phase flow in a choke

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Petroleum Science 2009年第1期6卷 91-97页

作者： Li Guomei Wang Yueshe He Renyang Cao Xuewen Lin Changzhi Meng Tao state key {2. of Multiphase Flow in {2. Engineering Xi＇an Jiaotong University Xi＇an Shaanxi 710049 China china Special Equipment Inspection and Research Institute Beijing 100013 China School of Transport ＆ Storage and Civil Engineering China University of Petroleum Qingdao Shandong 266555 China Petroleum Exploration and Production Research Institute Sinopec Beijing 100083 China

Chokes are one of the most important components of downhole flow-control equipment. The particle erosion mathematical model, which considers particle-particle interaction, was established and used to simulate solid particle movement as well as particle erosion characteristics of the solid-liquid two-phase flow in a choke. The corresponding erosion reduction approach by setting ribs on the inner wall of the choke was advanced. This mathematical model includes three parts： the flow field simulation of the continuous carrier fluid by an Eulerian approach, the particle interaction simulation using the discrete particle hard sphere model by a Lagrangian approach and calculation of erosion rate using semiempirical correlations. The results show that particles accumulated in a narrow region from inlet to outlet of the choke and the dominating factor affecting particle motion is the fluid drag force. As a result, the optimization of rib geometrical parameters indicates that good anti-erosion performance can be achieved by four ribs, each of them with a height （H） of 3 mm and a width （B） of 5 mm equaling the interval between ribs （L）.

关键词： Solid-liquid two-phase flow discrete particle hard sphere model choke erosion rate antierosion numerical simulation

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并联稳定平台电液驱动单元复合内模控制研究

中国机械工程 2017年第5期28卷 589-596页

作者：张立杰王力航李少华李永泉燕山大学河北省重型机械流体动力传输与控制重点实验室秦皇岛066004 先进锻压成形技术与科学教育部重点实验室(燕山大学) 秦皇岛066004 燕山大学河北省并联机器人与机电系统实验室秦皇岛066004

针对液压驱动舰船稳定平台样机的运动控制要求,提出了一种基于速度前馈结构的复合内模控制方案。以舰船稳定平台的单通道液压驱动单元为研究对象,采用机理建模和参数辨识相结合的方法得到了控制对象的数学模型,在模型的基础上完成了基... 详细信息

针对液压驱动舰船稳定平台样机的运动控制要求,提出了一种基于速度前馈结构的复合内模控制方案。以舰船稳定平台的单通道液压驱动单元为研究对象,采用机理建模和参数辨识相结合的方法得到了控制对象的数学模型,在模型的基础上完成了基于速度前馈结构内模复合控制器的设计,并对提出的控制方法进行了仿真和实验研究。仿真和实验研究结果表明:基于速度前馈结构的复合内模控制可以改善系统的跟踪性能,提高系统的抗干扰性和鲁棒性。

关键词：舰船稳定平台液压驱动单元速度前馈结构复合内模控制

RESEARCH ON VARIABLE VALVE SYSTEM BASED ON ELECTRO-HYDRAULIC DRIVE

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RESEARCH ON VARIABLE VALVE SYSTEM BASED ON ELECTRO-HYDRAULIC...

2.06年中国机械工程学会年会暨中国工程院机械与运载工程学部首届年会

作者： LIU Jinrong*, JIN Bo*, CHEN Ying*, WENG Zhentao *The state laboratory of{2. power transmission and control in ZheJiang University, hangzhou, china Ningbo HOYEA Machinery Manufacture Co.,Ltd, Ningbo, china

Variable valve technique can significantly improve the performance of the automobile engine and reduce pollution emission by varying valve timing, valve duration and valve lift. Variable valve system

关键词： Variable valve actuator electro-hydraulic drive valve lift valve timing control.

A Flexible Hingeless control Surface Inspired by Aquatic Animals

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Journal of Bionic Engineering 2010年第4期7卷 364-374页

作者： Zhenlong Wang,Jian Li,Guanrong Hang,Yangwei Wang state key {2. of Robotics and System,Harbin Institute of Technology,Harbin 150001,P.R.china [a] state key {2. of Robotics System Harbin Institute of Technology Harbin 150001 P. R. China

A flexible hingeless control surface model was proposed for motion control of Underwater Vehicles (UVs),which is inspiredby the flexible bending control surfaces of underwater creatures,such as fish and *** fluid Dynamics(CFD) simulation demonstrates that,in comparison with the hinged or rigid control surface,the proposed flexible bendingcontrol surface can suppress the flow separation so as to improve the turning performance.A prototype of the flexible controlsurface was fabricated,in which Shape Memory Alloy (SMA) wires were selected as the *** elastic energy storageand exchange mechanism was incorporated into the actuation of the control surface to improve the *** analysisof SMA wires was performed to find proper actuating ***-loop bending experiments were carried *** resultsshow that the proposed control surface can achieve the maximum bending angle of 104°.Moreover,the power and energyconsumption under different pulse conditions were compared.

关键词： bio-inspired flexible hingeless control surface CFD shape memory alloy wire underwater vehicle

Flow visualization of silicon-based micro pulsating heat pipes

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Science china(Technological Sciences) 2010年第4期53卷 984-990页

作者： QU Jian & WU HuiYing key laboratory for {2. Machinery and Engineering of Ministry of Education,School of Mechanical Engineering,Shanghai Jiaotong University,Shanghai 2.02.0,china 1. key laboratory for {2. Machinery and Engineering of Ministry of Education School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200240 China

Two sets of silicon-based micro pulsating heat pipes(SMPHPs) with trapezoidal cross section having hydraulic diameters of 352.μm(#1) and 394 μm(#2. respectively were fabricated for the first time using MEMS *** FC-72.as the working fluid,the start-up,steady operation state,as well as flow patterns were investigated using a CCD *** was found that the start-up process of these two SMPHPs was rather *** the start-up period,no nucleation was observed,and the vapor plugs at the evaporator U-bends were formed mainly due to the breakup of liquid *** the steady operation state,self-sustained oscillation with large amplitudes dominated the flow behavior when the inclination angle varied from 10° to 90°,but the nucleate boiling and bulk circulation were observed only in SMPHP #*** bubbly,slug/plug,annular/semi-annular,and wavy-annular flows were observed in both two SMPHPs,the injection flow only appeared in SMPHP #2.

关键词： micro pulsating heat pipe flow visualization start-up flow pattern injection flow

RESEARCH ON THE FLOW RATE CHARACTERISTIC OF PNEUMATIC COMPONENT AND CIRCUIT

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RESEARCH ON THE FLOW RATE CHARACTERISTIC OF PNEUMATIC COMPON...

第四届流体传动国际会议

作者： Zhao Ming Zhou Hong Chen Ying The state key Lab of {2. {2. transmission and control, Zhejiang University, hangzhou, P.R. china 31002. ** Festo (china) Ltd. Shanghai, P.R.china 2.12.6

This paper at first deals with the mathematic model of a pneumatic system and analyses the effects of some important parameters to the results of dynamic simulation;secondly, discusses the measure methods of component sonic conductance;at last carries out the relationship between the value of circuit flow-rate characteristic and that of each component according to the experience and measurement results.

关键词： pneumatic sonic conductance critical pressure ratio measure mathematic model