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文章阐述了涡街流量计在集中供热的园区企业能源计量中的应用,通过分析涡街流量计的工作原理,总结涡街流量计在不同介质的流体使用特性,重点阐述了在气体和蒸汽流量测量中注意事项。 相似文献
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弯管流量计在供热计量中的应用分析 总被引:2,自引:0,他引:2
文章介绍了弯管流量计在我公司热电机组一抽蒸汽出口计量的应用情况、弯管流量计在供热计量中的独特优点,并结合流体计量的理论对弯管流量计与孔板流量计、涡街流量计的性能差异作一简单分析。 相似文献
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一、引言涡街流量计的应用范围愈来愈广泛 ,并受到用户的欢迎。因为涡街流量计使用比较方便 ,量程比宽 ,压力损失小 ,更换检测元件无需重新标定 ,既有就地指示 ,又可进行运传 ,也省去了差压变送器 ,充分显示了它的优越性。涡街流量计是通过被检测介质产生的旋涡而产生脉冲信号 ,易受干扰 ,在投运中常遇到一些问题。本厂装了 10台LUGB系列涡街流量计 ,测量氯气和氯甲烷的流量 ,开始运行不正常 ,后来通过一段时间分析、改进、基本上能正常运行 ,本文介绍其投运过程。二、工作原理涡街流量计又称卡门旋涡流量计 ,它是利用流体自然振荡的原… 相似文献
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涡街流量计的原理、安装及改进1简单原理与测量方式涡街流量计之所以能测量,是基于卡门涡街理论。所谓卡门涡街现象,就是在流体中设置三角柱形漩涡发生体,流体流经发生体,则从发生体两侧交替地产生有规则的漩涡,称为卡门漩涡,漩涡在发生体下游非对称排列。如图1设... 相似文献
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本文简述涡街流量计的基本原理,分析了温度对传感器仪表系数的影响,给出了在测量高温流体时仪表修正的实用公式。 相似文献
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双锥流量计实验研究与计算模拟 总被引:1,自引:0,他引:1
提出的双锥流量计是一种新型的差压式流量计.采用CFD软件Fluent模拟计算管内流体绕流双锥节流件结构时的流动情况,得到流量与差压信号之间的关系.对几种特定直径比β为0.4,0.5,0.6的双锥流量计进行实验研究.结果表明,实验与模拟基本一致,并且具有量程比大,直管段要求短,压损小等优点. 相似文献
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在超声波气体流量计的实际测量中,多种不同因素引起流量测量的误差,其中流场分布是引起误差一个很重要的原因。采用多通道流量计可以较好地克服这一影响。但由于流体具有粘滞性,管道截面上不同半径处的流体速度各不相同,所以声通道测量的流体平均流速与实际管道中流体的面平均流速仍存在差异。对多通道超声波气体流量计的数学模型进行了研究,通过理论计算多通道超声流量计各通道的动力校正因子及权系数,由测得的若干超声传播路径上的线平均流速计算得到面平均流速,从而提高流量的测量精度。并将此应用于研制的四通道流量计中,进行了实验验证。 相似文献
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介绍了一种基于TDC(Time—to—Digital Converter)传输延迟线法的时差法外夹式V型超声流量计的设计方法,分析了设计中存在的同频噪声的生成原因以及它对测量精度的影响;对同频噪声信号和待测信号进行建模,运用最大似然估计法对噪声的幅度、相位参数进行估计,给出同频噪声的消除算法;在同频噪声消除后,对待测信号的幅度、相他参数进行估计,利用估计结果给出TDC测时方法是否可用的判决函数,并给出TDC测时方法无法使用时的解决方案. 相似文献
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Y. A. Sergeev S. Wang E. Meneguz C. F. Barenghi 《Journal of Low Temperature Physics》2007,146(3-4):417-434
Two-dimensional Lagrangian trajectories of the inertial particle in helium II are analyzed in the vicinity of the triple-vortex
structure, i.e. the superfluid vortex and the normal dipole-like vortex structure induced by the mutual friction. It is shown
that the vortices in the normal fluid can deflect the particle which otherwise would have collided with the superfluid vortex
and, provided that the relative velocity of the particle and the vortex is not too large, would have been trapped by it. A
geometrical impact parameter, which in the considered two-dimensional model, plays a r?le of the cross-section of particle–vortex
collision, is determined and calculated as a function of temperature, externally applied superfluid velocity, and the Stokes
number defined by the size of the local vortex structure, superfluid line velocity, and particle viscous response time. 相似文献
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《Advanced Powder Technology》2022,33(1):103349
Particle agglomeration in turbulent flows is an extremely complex process, and comprehensive study is beneficial to the development of turbulent agglomeration technology. The effects of vortex generator structure on particle agglomeration were investigated based on a combined computational fluid dynamics (CFD) and discrete element method (DEM) approach, including the geometric size, spanwise pitch, longitudinal pitch, row number, arrangement and form of the vortex generator. A dimensionless parameter K (the ratio of vorticity to strain rate, abbreviated as K) was defined to evaluate the agglomeration ability of the vortex generator, and the traditional agglomeration kernel function was modified by adding a correction coefficient α (agglomeration efficiency). By comparing the traditional agglomeration model and the modified agglomeration model with the experimental results, it showed that the modified agglomeration kernel model can simulate a result closer to the real agglomeration process. 相似文献
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Subhajit Dutta Chanchal Loha Pradip Kumar Chatterjee Anup Kumar Sadhukhan Parthapratim Gupta 《Advanced Powder Technology》2018,29(12):3357-3367
Gas-particle hydrodynamic behaviour inside a vortex chamber fluidized bed is studied numerically with respect to different design and operating conditions. A three-dimensional computational fluid dynamics (CFD) model of a cylindrical vortex chamber is developed. Simulations are carried out with particles and without particles. In order to understand the gas-particle flow behavior velocity distribution, particle volume fraction distribution, radial pressure distribution and axial pressure distribution inside the vortex chamber are analyzed in detail. Particles of different diameters are used and its effect on the gas-particle flow behaviour is studied. Design parameters like the number of gas inlet slots and slot width are varied and their impact on the hydrodynamics of the vortex chamber is investigated. The numerical model is validated by comparing the numerical results with experimental results reported in literature. 相似文献
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O. C. Idowu D. Kivotides C. F. Barenghi D. C. Samuels 《Journal of Low Temperature Physics》2000,120(3-4):269-280
Turbulence in helium II takes the form of a disordered tangle of quantised vortex line. The existing equation of vortex dynamics used by Schwarz and others to model the evolution of the vortex tangle does not distinguish between the large scale normal fluid velocity and the local variation of the normal fluid velocity introduced by the presence of quantised vortex lines. We derive a new vortex dynamics equation which allows the local normal fluid velocity to be determined by a modified Navier–Stokes equation. Together, the two equations form a self-consistent model to determine the coupled evolution of the normal fluid and quantised vortices. 相似文献
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Free convective heat transfer of a fluid in horizontal channels and above a horizontal surface is theoretically analyzed. The interaction of the fluid with the channel walls may be divided into two parts: formation of vortex flow cells, and heat transfer in the induced flow over the walls. 相似文献