共查询到18条相似文献,搜索用时 515 毫秒
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本文介绍了一种多级降压高压差调节阀的结构及工作原理。使用SolidWorks软件建立流道三维模型,并用网格划分软件对模型进行离散化处理,按实际工况参数设定边界条件,通过CFD流体动力学软件对阀门内部流场进行数值模拟。分别对阀门流量模拟计算,降压级数确定,对其压力场、速度场分布进行了分析。结果表明多级降压结构设计能够有效实现压力的渐变,有效地避免汽蚀现象的发生,防止冲刷、气蚀,延长使用寿命。 相似文献
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多级降压高压差调节阀设计 总被引:3,自引:0,他引:3
1 概述多级降压高压差调节阀用于精确控制高温、高压、高压差以及含有固体颗粒流体的流量和压力。该阀综合了普通式、多孔式和迷宫式低噪音调节阀的优点 ,能防止液体空化产生汽蚀 ,减小了高速流体对阀内件的冲刷 ,降低噪音。2 结构和工作原理多级降压高压差调节阀按阀芯结构可分为平衡型和不平衡型 2种。图 1为不平衡型阀芯结构。由于阀芯受不平衡力作用 ,因此克服高压差时需要较大的执行机构输出力。该阀内件为金属刚性结构 ,单个流体通道的流通截面积较大 ,且多级阀芯每个台阶处的刃口与套筒上的窗口在阀关闭时有剪切作用 ,故适合于对高… 相似文献
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针对超(超)临界电站锅炉调节阀在国产化进程中汽蚀失效问题,结合某电站调节阀出现的阀门管配系统底板汽蚀击穿现象,基于两相空化流动控制方程和Fluent流场数值模拟手段,展开对该调节阀及其管配系统流场特性分析并进行了结构优化。模拟结果表明,原锥压式调节阀在开度较小的情况下介质发生了严重的汽化现象,气化率达90%以上,介质速度高,以至于底板被冲击至击穿。根据电站锅炉用给水泵流量结构特性,提出一种笼罩式调节阀,优化结构在喉口区域含汽量减少了32.75%,盲板附近的速度降低79.03%,管配系统安全。模拟结果较好的展现了阀门流场的分布规律,为该类调节阀结构设计与优化提供了理论指导,对该类阀门国产化起到积极的意义。 相似文献
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喻临风何世权郎晨旭王佳琪 《流体机械》2023,(2):84-89
针对套筒式调节阀因工作时阀内流体压差过高、流速快,易产生阻塞流,导致在一定开度下,阀门流通能力降低,阀内噪声增大,致使套筒、阀芯、阀座损坏等问题,以DN80套筒式调节阀为研究对象,对套筒节流孔的形状进行优化,设计出2种不同形状的节流孔样式,对比分析3种不同形状的节流孔,采用计算流体动力学(CFD)方法对其内部流场进行数值模拟,分析调节阀流道内的速度分布云图、压力分布云图和流量特性曲线,并通过试验对比其流阻系数。结果表明,优化后的内缩式套筒结构在全开时,相较于初始结构降压能力提升约13.65%、最高降速约35%、流通能力提升约22.73%,并解决了在阀门开度为100%时阀体下腔处的回流现象。内缩式套筒结构具有更好的节流减压能力,能够安全可靠地应用于2种管线对接的工作状况,同时延长了阀门的使用寿命。 相似文献
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正随着国民经济的快速发展,各种工况对高压差的流动要求越来越多。调节阀作为一种节流装置,当压差较高时,流速往往较高,对节流处的冲击相对也大。若使用普通阀门,极有可能使阀门的振动较大。一方面使阀门内件耐不住冲刷而破坏;另一方面会产生较大的噪音,影响环境。故要求作为终端介质控制元件的调节阀也必须能适应高压差的流动。本文提出一种多级降压的结构来适应高压差的流动。 相似文献
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Cavitation is the main failure mode of coal liquefaction regulating valve, which seriously limits the service life of the regulating valve. In order to restrain cavitation in the regulating valve, a bio-inspired anti-cavitation structure inspired by the red willow of valve core is proposed. Distributions of pressure, velocity and vapor volume fraction in the bionic valve under different openings (30%, 40%, 50%, and 60%) and inlet pressures (2.0MPa, 3.0MPa, 4.0MPa, and 5.0MPa) are discussed. In addition, the parameters of bionic valve structure are optimized using NSGA-II algorithm, the field synergy principle is applied to evaluate the flow field optimization in the bionic valve. The results show that the cavitation area and cavitation length in these bionic structures are reduced significantly compared with the traditional smooth structure. And the anti-cavitation performance of the trench structure is the best, when the inlet pressure is 3 MPa and the opening is 30%, the vapor volume is 0.10 mm3, the vapor volume is reduced by 98.07% compared with traditional smooth structure. Convex hull structure is the second. When the inlet pressure is 5.0 MPa, the vapor volume of the traditional smooth structure is as high as 148 mm3, and the vapor volume of the convex hull structure is 35 mm3, the vapor volume of the trench structure is 19 mm3. Through the field synergy theory to evaluate the internal flow field, it is found that the effective viscosity coefficient in the traditional smooth structure regulating valve varies from 0.7 to 1.2, that of the bionic trench valve changes from 0.1 to 0.5, both the flow resistance and energy consumption in the trench structure valve are reduced. It is proved that the bionic trench structure of the valve core can effectively improve anti cavitation performance and optimize the internal flow resistance of the flow field, which is of great significance to the optimal design of the control valve. 相似文献
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Sleeve regulating valve is the key component of the industrial system. As the main cause of vibration and noise inside the sleeve regulating valve, cavitation also increases the energy loss when fluid flows through the valve. In this paper, in order to quantitatively analyze the influence of cavitation in the sleeve regulating valve, the effects of throttling windows number, pressure difference, valve opening and flow direction on the resistance coefficient are investigated with the application of cavitation model. By defining the cavitation influencing factor of the resistance coefficient, the calculation formula of the resistance coefficient when cavitation occurs in the sleeve regulating valve is proposed. The results show that when the fluid flows forward and the aggravation degree of cavitation increases, the energy loss also increases. And in the backward flow, the effect of cavitation on the resistance coefficient is related to the valve opening and the throttling windows number. This work is of significance for the optimization and design of sleeve regulating valve and pipeline system. 相似文献
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GONG Yongjun YANG Huayong WANG Zuwen 《机械工程学报(英文版)》2009,22(1):109-115
Due to the fire resistance and environmental compatibility, using water as the working fluid in hydraulic circuits is receiving an increasing attention by both manufactures and users. This hydraulic directional valve is developed. When new water hydraulic directional valve is designed and manufactured, this paper introduces a water hydraulic 2/2 directional valve and its principle. The valve is composed of a hydraulically operated seat valve and a magnetic 3/2 direction valve. Aimed at the serious leakage and impact generating easily in reversing suddenly, an improved structure of water space seal is changed to direct seal, compaction force between main valve spool and main valve pocket was logically designed and damper in pilot valve port is matched with sensitive cavity in main valve. From the view of flow control, the methods of cavitation resistance of the directional water hydraulic valve are investigated. The computational fluid dynamics approaches are applied to obtain static pressure distributions and cavitation images in the channel of the main stage of the valve with two kinds of structure. The results show that the method of optimized spout can effectively restrain cavitation. The work provides some useful reference for developing water hydraulic control valve with the Dower noise and lower vibration. Meantime, the structural parameters are optimized on the basis of information obtained from simulation. Static test, dynamic test and life test are accomplished, and the results show that the water hydraulic directional valve possesses good property, its pressure loss is 1.1 MPa lower, switching time is shorter than 0.025 s, and its strike crest is 0.8 MPa lower. The valve possess fine dynamic performance with the characteristic rapidly action and lower implusion. 相似文献