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Flow Resistance Modeling for Coolant Distribution within Canned Motor Cooling Loops

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Chinese Journal of Mechanical Engineering 2020年第1期33卷 210-220页

作者： Shengde Wang zhenqiang yao Hong Shen State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Taylor–Couette–Poiseuille(TCP)flow dominates the inner water-cooling circulation of canned motor reactor coolant *** research on TCP flow focuses on torque behaviors and flow regime transitions through experiments and ***,research on axial flow resistance in a large Reynolds number turbulent state is not sufficient,especially for the various flow *** study is devoted to investigating the influence of annular flow on the axial flow resistance of liquid in the coaxial cylinders of the stator and rotor in canned motor reactor coolant pumps,and predicting the coolant flow distribution between the upper coil cooling loop and lower bearing lubricating loop for safe *** axial flow resistance,coupled with the annular rotation,is experimentally investigated at a flow rate with an axial Reynolds number,Rea,from 2.6×10~3 to 6.0×10~3 and rotational Reynolds number,Ret,from 1.6×10~4 to 4.0×10~*** is revealed that the axial flow frictional coe cient varies against the axial flow rate in linear relation sets with logarithmic coordinates,which shift up when the flow has a higher *** examination of the axial flow resistance,with the Rea extending to 3.5×10~5 and Ret up to 1.6×10~5,by simulation shows gentle variation rates in the axial flow frictional coe cients against the *** relation curves with different Ret values converge when the Rea exceeds 3.5×10~5.A prediction model for TCP flow consisting of a polygonal approximation with logarithmic coordinates is developed to estimate the axial flow resistance against different axial and rotational Reynolds numbers for the evaluation of heat and mass transfer during transition states and the engineering design of the canned motor chamber structure.

关键词： Flow resistance Rotating effect Reynolds numbers Taylor–Couette–Poiseuille flow Canned motor

Experimental Study on Momentum Transfer of Surface Texture in Taylor-Couette Flow

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Chinese Journal of Mechanical Engineering 2017年第3期30卷 754-761页

作者： Yabo XUE zhenqiang yao De CHENG state key laboratory of mechanical system and vibration shanghai jiao tong universityShanghai 200240China school of mechanical engineering shanghai jiao tong universityShanghai 200240China

The behavior of Taylor-Couette （TC） flow has been extensively studied. However, no suitable torque prediction models exist for high-capacity fluid machinery. The Eckhardt-Grossmann-Lohse （EGL） theory, derived based on the Navier-Stokes equations, is proposed to model torque behavior. This are the significant energy theory suggests that surfaces transfer interfaces between cylinders and annular flow. This study mainly focuses on the effects of surface texture on momentum transfer behavior through global torque measurement. First, a power-law torque behavior model is built to reveal the relationship between dimensionless torque and the Taylor number based on the EGL theory. Second, TC flow appa- ratus is designed and built based on the CNC machine tool to verify the torque behavior model. Third, four surface texture films are tested to check the effects of surface texture on momentum transfer. A stereo microscope and three-dimensional topography instrument are employed to analyze surface morphology. Global torque behavior is measured by rotating a multi component dynamometer, and the effects of surface texture on the annular flow behavior are observed via images obtained using a high-speed camera. Finally, torque behaviors under four differentsurface conditions are fitted and compared. The experi- mental results indicate that surface textures have a remarkable influence on torque behavior, and that the peak roughness of surface texture enhances the momentum transfer by strengthening the fluctuation in the TC flow.

关键词： Torque behavior - Momentum transferbehavior Surface texture Experimental study TaylorCouette flow (TC flow)

Impedance Analysis of Forging Process and Strategy Study on Compliance for Forging Manipulator

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Chinese Journal of Mechanical Engineering 2013年第4期26卷 651-658页

作者： ZHANG Pu yao zhenqiang DU Zhengchun State Key Lab of Mechanical System and Vibration Shanghai Jiao Tong University

In the field of heavy forging, there are numerous researches on deformation rule in forging process by FEM simulation, however, not many scholars take the equipment constraint and the mutual reaction load between the forging manipulator clamp and the forging blank into account, which will impact on safety of manipulator body and quality of forging blank. This paper presents an impedance model to describe the load and formulates compliance strategies correspondingly to reduce the mutual reaction load for forging manipulator. Firstly, an FEM model of forging process is built. Meanwhile, the clamp of forging manipulator is added to the model as movement constraint and interaction part between the manipulator and the forming process. Secondly, a typical forging process is simulated by changing the movement constraint, and then an impedance model is established to describe the relationship between the load and movement constraint. Finally, two kinds of compliance strategies are formulated according to the impedance model, one is called free compliance, and the other is initiative/passive compliance. The simulation results show that compliance strategies reduce the load amounting to 5 000 kN in z direction between the manipulator clamp and the forging blank obviously, which may lead to serious accidents, such as the capsizing of forging manipulator, the fracture of manipulator clamp, and so on. The proposed research simulates the more real forging process, gets the initiative/passive compliance strategy which is more simple and suitable to the real producing and better for forming a forging process planning and control system in the modern production, and improves the quality and efficiency of heavy forging.

关键词： forging impedance compliance manipulator

Oscillatory Failure Detection for Flight Control System Using Voting and Comparing Monitors

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第5期36卷 817-827页

作者： XUE Ying yao zhenqiang Shanghai Aircraft Design and Research Institute Shanghai 200210P.R.China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240P.R.China

Oscillatory failure cases(OFC)detection in the fly-by-wire(FBW)flight control system for civil aircraft is addressed in this ***,OFC is ranked four levels:Handling quality,static load,global structure fatigue and local fatigue,according to their respect impact on ***,we present voting and comparing monitors based on un-similarity redundancy commands to detect ***,the associated performances,the thresholds and the counters of the monitors are calculated by the high fidelity nonlinear aircraft ***,the monitors of OFC are verified by the Iron Bird Platform with real parameters of the flight control *** results show that our approach can detect OFC rapidly.

关键词： oscillatory failure fly-by-wire flight control system monitor voting

Experimental study on laser shock processing of brass

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Journal of University of Science and Technology Beijing 2007年第6期14卷 529-532页

作者： Fei Wang zhenqiang yao Qilin Deng School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200240 China

Laser shock processing （LSP） is a new surface treatment technique for improving hardness, wear resistance, and fatigue. In this paper, basic theories were introduced and the influence of laser pulse intensity on the laser shock processing of brass specimens was investigated by experiments. Microhardness, roughness, microstructure, wear resistance, friction coefficient evolution, and residual stress were examined with different laser pulse intensities of LSP. The results show that the microhardness increases after LSP treatment, and the higher the pulse intensity, the higher the microhardness. Though the microstructure shows no remarkable change, the roughness and wear resistance increase with the increase in pulse density. Laser shock processing has great potential as a means to improve the mechanical properties of components.

关键词： laser shock processing microhardness roughness wear resistance compressive residual stress

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机械科学与工程研究中的创新能力

机械工程学报 2000年第2期36卷 9-10,20页

作者：姚振强上海交通大学机械工程学院上海200030

分析探讨了提高科技创新能力的关键要素。创新教育首先要培养创新意识。要用敏锐的洞察力去发现问题、形成并提出问题。要有丰富的知识，以及获取、处理信息并将其转换为知识的能力。要有科学研究的素质和创造性思维的能力。要善于通过... 详细信息

分析探讨了提高科技创新能力的关键要素。创新教育首先要培养创新意识。要用敏锐的洞察力去发现问题、形成并提出问题。要有丰富的知识，以及获取、处理信息并将其转换为知识的能力。要有科学研究的素质和创造性思维的能力。要善于通过高度的科学或哲学概括，建立不同现象间的内在关联，以获得创新。要善于利用发散或反向思维取得创新成果。

关键词：创新能力机械科学机械工程

Hydroxychloroquine and a low antiresorptive activity bisphosphonate conjugate prevent and reverse ovariectomy-induced bone loss in mice through dual antiresorptive and anabolic effects

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Bone Research 2024年第3期12卷 734-744页

作者： zhenqiang yao Akram Ayoub Venkatesan Srinivasan Jun Wu Churou Tang Rong Duan Aleksa Milosavljevic Lianping Xing Frank H.Ebetino Alison J.Frontier Brendan F.Boyce Department of Pathology and Laboratory Medicine University of Rochester Medical CenterRochesterNY 14642USA Department of Chemistry University of RochesterRochester NY14627USA School of Arts and Sciences University of RochesterRochester NY14627USA BioVinc LLCPasadenaCA 91107USA

Osteoporosis remains *** most widely used antiresorptive agents,bisphosphonates(BPs),also inhibit bone formation,while the anabolic agent,teriparatide,does not inhibit bone resorption,and thus they have limited effica... 详细信息

关键词： res conjugate phosphonate

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调整时间与顺序相关的等同并行机调度

机械工程学报 2011年第16期47卷 160-165页

作者：胡大勇姚振强上海交通大学机械系统与振动国家重点实验室上海200240

调整时间与顺序相关的等同并行机调度在生产服务业与制造业中有着十分广泛的应用背景,具有计算复杂性的主要特点。调整时间与顺序相关的等同并行机调度是将被加工工件集的各工件分配给等同并行机资源,并安排工件的加工次序。它是决策的... 详细信息

调整时间与顺序相关的等同并行机调度在生产服务业与制造业中有着十分广泛的应用背景,具有计算复杂性的主要特点。调整时间与顺序相关的等同并行机调度是将被加工工件集的各工件分配给等同并行机资源,并安排工件的加工次序。它是决策的一种形式,其目的是优化一个或多个目标。研究以最小化被加工工件最大完工时间为目标的调整时间与顺序相关的等同并行机调度,建立该问题的数学规划模型,根据问题的结构特点开发基于两段式染色体表达的遗传算法以获得该问题的近似最优解;在所建立数学规划模型的基础上,引入所求解问题的下界对近似最优解的质量进行评价。对具有不同规模的问题实例进行计算试验,计算结果表明所设计的遗传算法能够在可接受的计算时间内获得合理的解。

关键词：等同并行机调度调整时间与顺序相关数学规划模型下界遗传算法

基于动力学响应的球头刀五轴铣削表面形貌仿真

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机械工程学报 2013年第6期49卷 171-178页

作者：梁鑫光姚振强上海交通大学机械与动力工程学院上海200240 上海交通大学机械系统与振动国家重点实验室上海200240

针对自由曲面球头刀五轴铣削中刀具与工件复杂的位姿关系,利用球头铣削刃的三维次摆线轨迹,提出一种在工件表面等距离间隔缓存残留高度、在刀具端等时间间隔缓存振动响应的双缓存离散机制,分别实现五轴铣削中的名义加工表面形貌建模与... 详细信息

针对自由曲面球头刀五轴铣削中刀具与工件复杂的位姿关系,利用球头铣削刃的三维次摆线轨迹,提出一种在工件表面等距离间隔缓存残留高度、在刀具端等时间间隔缓存振动响应的双缓存离散机制,分别实现五轴铣削中的名义加工表面形貌建模与系统动态响应轨迹仿真。在此基础上,以切削刃经过工件表面残留区域的时间信息为纽带,利用系统瞬时动态位移响应的插值信息对已加工表面法向残留高度进行修正,建立考虑铣削系统动力学响应的已加工表面形貌预测模型。以变切深、变转速、恒定的刀具倾角与每齿进给量所进行的验证试验表明,提出的球头刀五轴铣削表面形貌建模方法可有效预测颤振工况与稳定铣削工况的加工表面形貌与纹理特征。

关键词：球头刀五轴铣削表面形貌仿真动态响应