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Solid-liquid flow characteristics and sticking-force analysis of valve-core fitting clearance

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第12期24卷 1096-1105页

作者： jin-yuan qian Jiaxiang XU Fengping ZHONG Zhenhao LIN Tingfeng HUA Zhijiang jin Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou 310027China Zhejiang Academy of Special Equipment Science Hangzhou 310009China Institute of Wenzhou Zhejiang UniversityWenzhou 325036China

External contamination particles or wear particles corroded by a valve body are mixed into the fluid. As a result, when the fluid enters the fitting clearance of the valve core, it can cause an increase in resistance and lead to sticking failure of the valve core. This paper analyzes solid-liquid flow characteristics in fitting clearances and valve-core sticking based on the Euler-Euler model, using a typical hydraulic valve as an example. The impact of particle concentration and diameter on flow characteristics and valve-core sticking force was analyzed. The highest volume fraction of particles was in the pressureequalizing groove(PEG), with peak values increasing as the particle diameter increased. The sticking force increased with increasing particle concentration. When the particle diameter was 12 μm, the sticking force was the largest, making this the sensitive particle diameter. Particle distribution and valve-core sticking force were compared for oval, rectangular, and triangular PEGs. The fluid-deflection angles in oval and rectangular PEGs were larger, and their values were 32.83° and 39.15°, respectively. The fluid-deflection angle in the triangular PEG was relatively small, less than 50% that of the oval or rectangular PEGs. The particle-volume-fraction peaks in oval, rectangular, and triangular PEGs were 0.0317, 0.0316, and 0.0312, respectively. The sticking forces of oval, rectangular, and triangular PEGs were 4.796, 4.802, and 4.757 N, respectively when the particle diameter was 12 μm. This work provides a reference for design and research aimed at reducing valve-core sticking.

关键词： Solid-liquid flow characteristics Valve core Sticking force Euler-Euler model

Numerical simulation and structure improvement of double throttling in a high parameter pressure reducing valve

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第2期14卷 137-146页

作者： Zhi-jiang jin Lin WEI Li-long CHEN jin-yuan qian Ming ZHANG Institute of Chemical Machinery and Process Equipment Zhejiang University Hangzhou Worldwides Valve Co. Ltd.

In this paper, a new pressure reducing valve （PRV） with an orifice plate is proposed. The main objective is to explain the mechanisms of pressure reduction and energy conversion in the new PRV. A numerical simulation method was used to investigate the PRV internal flow field and to analyze the throttling effects of the orifice plate and the transform of thermal parameters as outlet pressure, outlet temperature, velocity, and superheat. A structure improvement method for the valve body and orifice plate is put forward to reduce energy loss. The governing equations for internal flow numerical simulation are composed of the continuity, momentum, energy and k-e transport equations, based on isotropic eddy viscosity theory. Different valve plug displacement models were built to describe the double throttling process. Our analysis shows that the steam pressure drops twice and the degree of superheat increases. There are also lots of eddies which clog the flow channel and disturb the steam flow in the valve cavity after the valve plug and the outlet cavity. After modifying the structure, the numerical results show a better performance of steam flow.

关键词： Numerical simulation Pressure and temperature reducing system Pressure reducing valve (PRV) Double throttling Structural improvement

Study on the Relation Bet ween Magnetic Moment and Charge Transfer of Metallic Glasses By LCAO-X_(α) Method

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Chinese Physics Letters 1996年第3期13卷 196-198页

作者： LIU Hong-lin CHEN Nian-yi NI Min HE Li-ming jin qian-yuan Shanghai Institute of Metallurgy Chinese Academy of SciencesShanghai 200050 Department of Physics East China University of Science and TechnologyShanghai 200237

The calculations of the clusters,T_(27) and T_(27)B_(7)(T=Fe,Co and Ni),modelling metallic glasses have been performed using the quantum chemical linear combination of atomic orbitals(LCAO)-X_(α) *** argument about t... 详细信息

关键词： (α) glasses clarified

A parametric study on unbalanced moment of piston type valve core

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2021年第4期22卷 265-276页

作者： jin-yuan qian Juan MU Cong-wei HOU Zhi-jiang jin Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

In this paper,the piston type valve core and the unbalanced moment on its bottom are *** decrease the influence of non-common geometrical factors,a simplified model of the piston type globe valve is proposed in this *** on the computational fluid dynamics(CFD)method,the effects of different geometrical parameters on the unbalanced moment existing on the bottom of the valve core,which include the bending radius of the inlet flow channel,the diameter of the special-shaped pipe,and the height of the valve core,are ***,the effects of geometrical parameters on the unbalanced moment on the bottom of the valve core are clarified by correction and variation classification and provide a basis for further optimizing the structure of the piston type *** results show that the unbalanced moment decreases with the increase of the bending radius of the inlet flow channel,but increases with the increase of the diameter of the special-shaped pipe and the height of the valve ***,the relation between the unbalanced moment and flow rate is proposed.

关键词： Piston type valve core Unbalanced moment Geometrical parameters Computational fluid dynamics(CFD)

纳米流体在微尺度特斯拉阀中流动的数值研究（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2019年第1期20卷 50-60页

作者： jin-yuan qian Min-rui CHEN Xue-ling LIU Zhi-jiang jin Institute of Process Equipment College of Energy Engineering Zhejiang University MOE Key Laboratory of Efficient Utilization of Low and Medium Grade Energy Tianjin University

目的:微通道以其效率高、体积小等特点在许多领域有着越来越广泛的应用。特斯拉阀是一种没有运动部件的止回阀,在微流动控制领域有着明显的优势。大量研究表明,将纳米流体运用到微尺度通道中可明显提高换热效率。本文将二者结合,研究Al2... 详细信息

目的:微通道以其效率高、体积小等特点在许多领域有着越来越广泛的应用。特斯拉阀是一种没有运动部件的止回阀,在微流动控制领域有着明显的优势。大量研究表明,将纳米流体运用到微尺度通道中可明显提高换热效率。本文将二者结合,研究Al2O3-水纳米流体在微尺度特斯拉阀中的流动特性,为微尺度特斯拉阀以及纳米流体的进一步研究提供参考。创新点:1.将特斯拉阀应用于纳米流体的微流动控制中;2.研究不同的操作条件和不同的介质特性对纳米流体在微尺度特斯拉阀中流动特性的影响;3.研究纳米流体在微尺度特斯拉阀中不同流动方向的流体分布和压力情况,并根据特斯拉阀的压降比(反向流动压降/正向流动压降)来分析特斯拉阀对微流动的控制效果。方法:1.建立微尺度特斯拉阀的三维模型;2.通过有效性验证的数值方法,在不同操作条件和不同流动介质特性的情况下,模拟纳米流体在微尺度特斯拉阀中正反两个方向的流动;3.根据流体在流动过程中的分布以及压力的变化情况,分析温度、流体流量和纳米颗粒体积分数对纳米流体在微尺度特斯拉阀中流动特性的影响。结论:1.纳米流体在特斯拉阀中正向流动时,大部分流体进入了分叉段中的直通道;而反向流动时,大部分流体进入了分叉段中的弧形通道,并且随着流量、温度和纳米颗粒体积分数的增加,主流量的百分比增加。2.当纳米流体反向流动时,在弧形通道出口处的射流对压降的影响非常明显,这是导致反向流动压降大于正向流动的重要原因。3.特斯拉阀的压降比受流量的影响最显著;在本文的研究范围内,压降比随着流量的增加而线性增加。

关键词：纳米流体特斯拉阀纳米颗粒计算流体动力学

阀芯形状对套筒式调节阀内空化流动的影响研究（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2020年第1期21卷 1-14页

作者： Zhi-jiang jin Chang QIU Cheng-hang JIANG Jia-yi WU jin-yuan qian Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou 310027China Hangzhou Special Equipment Inspection&Research Institute Hangzhou 310051China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

目的:套筒式调节阀内空化的发生不仅会增加整个管路系统的能量损耗,而且会造成阀体及管路的失效破坏。本文旨在探讨四种不同形状的阀芯对套筒式调节阀内不同阀芯位移工况下的空化流动及空化强度的影响,为套筒式调节阀的优化设计及空化... 详细信息

目的:套筒式调节阀内空化的发生不仅会增加整个管路系统的能量损耗,而且会造成阀体及管路的失效破坏。本文旨在探讨四种不同形状的阀芯对套筒式调节阀内不同阀芯位移工况下的空化流动及空化强度的影响,为套筒式调节阀的优化设计及空化控制提出建议。创新点:1.根据四种不同形状的阀芯,研究套筒式调节阀内阀芯形状对流动及空化特性的影响;2.建立数值模型,对套筒式调节阀在不同阀芯形状和不同阀芯位移条件下进行流动及空化分析。方法:1.建立带有不同形状阀芯的套筒式调节阀数值计算模型,并比较分析阀芯形状对阀内速度、压力及空化情况的影响(图4,8和11);2.建立不同阀芯位移条件下的阀门数值模型,比较分析阀芯位移对阀内速度、压力及空化情况的影响(图6和10);3.建立不同形状阀芯及不同阀芯位移下的阀门模型,分析阀芯形状和位移对阀内流动及空化特性的综合影响(图7和13)。结论:1.在四种不同形状阀芯的条件下,高速流动区域和空化发生区主要位于套筒与阀芯之间的间隙;2.在直筒形和椭球形阀芯条件下的阀内空化强度明显强于平底形和圆台形阀芯条件下的空化强度,因此平底形和圆台形阀芯在空化控制方面具有更好的效果;3.在四种不同形状阀芯的条件下,随着阀芯位移的增加,阀内由空化产生的蒸汽总体积先增加后减少。

关键词：套筒式调节阀空化强度阀芯形状总体蒸汽体积

Effect of droplet superficial velocity on mixing efficiency in a microchannel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第10期23卷 783-794页

作者： jin-yuan qian Lei ZHAO Xiao-juan LI Wen-qing LI Zhi-jiang jin Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

In this study, droplet characteristics including droplet length and formation time, and mixing efficiency in droplets were investigated via the volume of fluid(VOF) method coupled with a user defined scalar(UDS) model. A cross-shaped junction with a square cross-section was designed and used for droplet formation. An initial arrangement which differed from that of a conventional operation was adopted. Results show that when the droplet superficial velocity is constant, the exchange between the dispersed phase velocity and the continuous phase velocity has a marginal effect on the droplet formation ***, the exchange has a great effect on droplet length. These findings provide a valuable guide for future operation of droplet formation. In addition, the results show that the mixing efficiency in the droplet forming stage can be classified into time-dominated and length-dominated regimes according to the droplet superficial velocity. When a droplet flows in a microchannel,a higher droplet superficial velocity increases mixing efficiency due to the faster inner circulation and shorter droplet length.

关键词： Droplet characteristics Mixing efficiency Inner circulation Droplet superficial velocity

Seal contact performance analysis of soft seals on high-pressure hydrogen charge valves

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第4期23卷 247-256页

作者： Zhen-hao LIN Long-jie YU Ting-feng HUA Zhi-jiang jin jin-yuan qian Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou310027China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310027China Institute of Wenzhou Zhejiang UniversityWenzhou325036China

The charge valve is an important element in the charging port of a high-pressure hydrogen storage cylinder(HP-HSC).It is normally closed after the HP-HSC is filled with *** the seal of the charge valve is damaged,it will seriously affect the stable operation of the hydrogen supply system and may even cause safety ***,the seal performance of the charge valve is *** this paper,finite element analysis(FEA)is carried out to analyze the seal contact performance of hydrogenated nitrile rubber(HNBR)gaskets in the seal pair of a charge *** effects of different pre-compressions,seal widths,and hydrogen pressures on the seal contact performance of the charge valve are *** contact pressure on the seal surface increases with the increase of *** a pre-compression of 2.5 mm,the maximum contact pressure without and with hydrogen pressure are 68.51 and 107.38 MPa,respectively.A contact gap appears in the inner ring of the seal surface with pre-compression below 0.15 *** contact gap occurs between the entire seal surface with a seal width of1 *** contact pressure on the seal surface and the width of the separation area between the seal surfaces increase with the increase of the seal *** contact gap between the seal surfaces is zero with a width of 2.5 *** width of the separation area between the seal surfaces decreases with the decrease of the hydrogen *** width of the separation area is reduced from 0.5 mm at 35 MPa to 0.17 mm at 15 *** work can be useful for improvement of the seal performance and of the design of the charge valve used in the HP-HSC.

关键词： Charge valve Seal contact performance High-pressure hydrogen storage cylinder(HP-HSC) Finite element analysis(FEA)

Practice of flow control and smart valves

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第4期23卷 243-246页

作者： jin-yuan qian Wei WU Min CHENG Jun-hui ZHANG Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou 310027China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China School of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China Institute of Mechatronics and Control Engineering Zhejiang UniversityHangzhou 310027China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

Introduction The usual metaphors of“heart”and“throat”indi-cate the importance of pumps and valves in industrial systems including petroleum,chemical,metallurgy,aviation,and *** the continuous penetra-tion of the industrial internet,the miniaturization,digi-tization,multi-functionalization,and systemization of valves have become very important(Si et al.,2020;Chang et al.,2021;Pang et al.,2021;Bonilla et al.,2022;yuan et al.,2022;Zhao et al.,2022).

关键词： smart internet flow