V锥流量计与孔板流量计的比较

V锥流量计和孔板流量计同属于差压类流量计,但是由于内部结构不同,V锥流量计和孔板流量计各有特点。该文结合实例,对V锥流量计和孔板流量计的优缺点做了详细的比较。     

一种新式差压流量计的设计与应用

该文分析了影响蒸汽流量准确计量的主要因素,介绍了传统的蒸汽流量计如孔板流量计和涡街流量计的使用局限性,详细介绍了一种基于皮托管原理的新式差压式流量计的设计原理、结构特点及其标定方法,通过实例给出了典型蒸汽工况下选择流量计的考虑因素,以及应用这种新式差压式流量计的选型和计算过程。     

光纤光栅内锥式流量计的研究

光纤光栅传感技术具有光纤传感技术的所有优点,内锥式流量传感器具有量程比大,压损较小,耐高温高压,要求前后直管段长度小的特点。将光纤光栅和内锥流量传感器结合组成了新型的光纤光栅内锥式流量计,介绍了光纤光栅和内锥式流量传感器的工作原理,光纤光栅内锥式流量计的组成。实验数据和结论。     

Response of a dual triangulate bluff body vortex flowmeter to oscillatory flow

In this paper, on an experimental facility, the measurement characteristics of a diameter 50 mm dual triangulate bluff body vortex flowmeter in steady flow and oscillatory flow were investigated. Then, the Hilbert Huang Transformation (HHT) method was used to assess the anti-interference performances and the vortex street stability in oscillatory flow for the dual triangulate bluff body vortex flowmeter and a single bluff body vortex flowmeter. Offline simulation was carried out on the anti-interference performances of the dual triangulate bluff body vortex flowmeter signal noise in oscillatory flow by the method of the EMD-scales filter. The major findings are: (a) in most case, the EMD-scales filter may be as good at de-noising effect for the dual bluff body vortex flowmeter in oscillatory flow than that for the single bluff body vortex flowmeter in oscillatory flow. The vortex street stability in oscillatory flow for the dual bluff body is similar to that for the single bluff body. (b) In some special case, the EMD-scales filter is unable to play a better de-nosing role for the dual bluff body vortex flowmeter in oscillatory flow. The invalid condition of the EMD-scales filter for the dual bluff body vortex flowmeter in oscillatory flow is different to that of the single bluff body vortex flowmeter and it was advanced in this paper. (C) The vortex street stability for the dual bluff body vortex flowmeter is better than that for the single bluff body vortex flowmeter.     

基于PIC18F452的流量计的设计与实现

介绍一种以PIC18F452单片机为核心的智能流量计。通过测量来自涡街的信号频率,计算得到流体的瞬时流量和累积量,并进行显示。流量计具有CAN通信接口,多个流量计可以组成CAN通信网络,实现对流量的多点监测。文中详细阐述了流量计的工作原理,给出了硬件原理图及软件流程图。     

电磁流量计在酸性废水处理中的应用

介绍Khrone公司生产的电磁流量计在不锈钢酸性废水处理中的应用,探讨了电磁流量计的测量原理和结构,以及安装技术要求和常见的故障,对于掌握该流量计的使用方法和性能具有一定的指导作用,为电磁流量计在线测量提供了一定的参考。     

基于HART协议的温压补偿型涡街流量计的设计

在传统涡街流量计的基础上，设计出符合HART协议的两线制一体化温压补偿型涡街流量计。介绍了传感器工作原理和温压补偿方法，给出系统的设计结构和硬件电路组成。着重阐述了HART协议在涡街流量计中的软硬件实现方法．并通过HART调制解调器实现了仪表与上位机之间的双向数字通讯。     

涡街流量计旋涡上举力系数的研究

在涡街流量计中,频率感测元件是其核心部件,旋涡上举力的大小直接影响到感测元件的灵敏度。本文通过实验与研究给出了比较准确的举力系数,为感测元件的设计提供了依据。     

超声波气体流量计检测精度影响因素分析

在天然气的管道运输过程中,提高气体流量测量的精度是提高运输效率、避免安全事故发生的关键技术。利用流体力学仿真（CFD）方法建立组合双弯管及变径管道模型,定量计算修正系数,对双声道超声波流量计结构和安装位置对于管道内气体速度场的影响进行研究。通过仿真得出超声波流量计的最优声道位置,并结合实验验证了仿真结果的可信性。模拟结果表明,双弯管和变径管与超声波流量计的安装位置至少为10D才能保证流体充分流动;通过修正系数随雷诺数的变化情况得出双声道超声波流量计的最优声道位置为距管道截面中心0.25D处。研究结论对于不同性质气体的流量检测同样适用,为工业中气体运输检测精度的提高以及超声波流量计的优化提供了依据。     

德尔塔巴流量计在流量测量中的应用

介绍了一种用于流量测量的德尔塔巴流量计,简述了德尔塔巴的测量原理以及基本结构,详细的介绍了德尔塔巴流量计的特点并与孔板、转子流量计、涡街流量计等常见的流量仪表进行了对比,通过实例阐述了德尔塔巴在实际工程应用中的价值。     

气体涡轮流量计性能优化的模拟与实验研究

以TRZ80气体涡轮流量计为研究对象,采用数值模拟与实验测试相结合的方法,提出了前整流器和后导流体的结构优化方案。通过对结构优化前后流量内部流场特征的分析,揭示了流量计结构与性能优化背后确切的流体力学机制。研究结果表明：前整流器和后导流体区域的压降突变与后导流体尾部的涡旋结构和回流现象是影响流量计计量性能的主要机制。优化的流量计结构可以明显减弱压降突变、涡旋结构与回流现象。优化的流量计结构既可以显著降低流量计的压力损失,又可以明显提高流量计的测量精度与稳定性,其压力损失和线性度误差分别降低了约48.58%和32.43%。研究结果有助于为今后开发与量产计量性能更好的气体涡轮流量计提供理论指导和技术支持。     

A regression-based model for prediction of flowmeters calibration cost in oil and gas industry

Measurement of liquid flowmeters is one of the most expensive processes in the oil and gas industry. Estimating calibration costs for such flowmeters in the oil and gas industry is complicated task for the decision-making team. The difficulties arise as a result of the presence of numerous uncertain factors that influence calibration charges such as the fabrication of special tools and spools. Consequently, this paper proposes a data-driven approach for estimating the calibration costs of flowmeters in oil and gas industry. A regression-based model is developed to predict the future calibration costs of flowmeters. The factors that affect the costs of calibrating flowmeters are identified from literature and interviewing local experts. The results indicated that the most important factors influencing the cost of liquid flowmeter calibration include flowmeter size, calibration method, flowmeter type, flowmeter class and calibration factor. The developed model is validated using 577 new data points of flowmeters calibration costs. The findings showed the uncertainty of the proposed model within 98% confidence level. An accurate calibration cost for liquid flowmeter will help to manage the operational and services costs.     

孔口流量计正压测试夹具和可膨胀系数的研究

孔口流量计是标准孔板流量计的特殊使用形式,为环境监测领域中常用流量测量元件。孔口流量计在校准时按上游入口压力的不同,其校准方法分为微正压和微负压两种校准工况。两种工况均为国家标准和规范推荐方法,但校准出的流量系数差距达10%。夹具引入的附加差压和仪表流量系数线性度误差是导致两种校准工况流量系数偏差的原因。通过CFD仿真研究,设计对被校准孔口流量计上游压力影响较小的夹具形式和结构参数。在仿真数据的基础上计算得到适用于常用管径和雷诺数范围的孔口流量计的可膨胀修正系数公式。运用上述成果并进行试验验证,正压和负压校准流量系数的差距减小至±0.5%以内。校准流量范围内孔口流量计流量系数线性度也有0.1%左右的提升。     

A mini fluidic oscillating flowmeter

This paper presents a mini fluidic oscillating flowmeter. This device is composed of three microfluidic laminar bistable amplifiers. The microfluidic amplifiers are connected in such a way that the measured flow through the mini fluidic oscillating flowmeter generates a periodical pressure signal with a high value of SNR (signal to noise ratio). The frequency of the pressure signal is proportional to the measured flow. The mini fluidic oscillating flowmeter works with gas or liquid. To calibrate the mini fluidic oscillating flowmeter, for gas flows, a volumetric flowmeter was used. To calibrate it for liquid flows, an experimental test bench was realized. The gas operating range of the mini fluidic oscillating flowmeter is up to Re=1500 starting from Re=200; the liquid operating range is up to Re=5700 starting from Re=170. The maximum error of the measurement is <2% of the full scale value, the reading error is <3% for gas flows and <3.8% for liquid flows.     

Particle image velocimetry flowmeter for natural gas applications

Ultrasonic flowmeters are currently used in the measurement of large natural gas flow. However, their high sensitivity to noise signals can cause measurement errors and direct economic losses. Particle image velocimetry (PIV) measurement technology has several advantages, including convenient installation and maintenance, and strong anti-interference ability, thereby presenting an innovative idea for its application in the field of flow measurement. In this paper, a cyclic integration method is proposed for the application of PIV technology in flow measurement of natural gas. The results show that PIV flowmeter and ultrasonic flowmeter are basically consistent, and the maximum deviation is about 2%. confirming the feasibility of the PIV flowmeter. Therefore, this study provides a theoretical and technical reference for the development of a PIV flowmeter for natural gas.     

电导式相关流量计应用于油井井下流量测量

本文提出了一种新型的电导相关流量计,其敏感元件采用两个电导传感器,该流量能够应用于高含水油井的油水两相流流量测量,在多相流动实验装置上进行的实验表明,该流量计测量的流速范围宽,线性好,该流量计已经在大庆油田进行现场试验,使用该流量计在井下测量的油水的总流量与地面计量结果对比良好。     

影响科氏质量流量计振动管磨损的若干因素研究

黏性流体和被测流体中的固相颗粒对科里奥利质量流量计(以下简称科氏质量流量计)振动管内壁均存在磨损作用,振动管的磨损状态对流量计离线标定、故障诊断和基于振动的流体黏度的测量存在一定的影响.基于固相颗粒对管道的磨损机理,讨论了影响固相颗粒对流量计振动管磨损的几种因素.提出了减小振动管磨损速度和延长流量计使用寿命的措施建议.     

节流型流量计的比较选型及应用

从原理、计算方法和性能等方面对目前应用广泛的几种流量计进行比较和分析,得出了节流型流量计是一种经济性好、稳定性好、使用方便的流量计的结论。介绍了几种节流型流量计的选型方法,具体介绍了新型节流装置德尔塔巴流量计在某选矿厂浮选作业空气流量检测中的应用情况。     

Theoretical study of vertical slug flow measurement by data fusion from electromagnetic flowmeter and electrical resistance tomography

Electrical resistance tomography (ERT) can be used to obtain the conductivity distribution or the phase distribution of gas/liquid flows (e.g. slug flow). Using proper parameter models and flow regime identification models, the measurement of phase size, void fraction, and pattern recognition can be realized. Electromagnetic flowmeters have been used to measure conductive single-phase liquid flows. However, neither ERT nor electromagnetic flowmeters (EMF) can provide accurate measurement of gas/liquid two-phase flows. This paper presents an approach to fuse the information from ERT and an electromagnetic flowmeter. A model for the measurement signal from the electromagnetic flowmeter has been developed based on the flow pattern and the phase distributions, which are obtained from the reconstructed images of ERT, aiming to reduce the measurement error of the electromagnetic flowmeter and enhance the measurement accuracy. Through the simulation research of virtual current density distribution, the feasibility of fusion of electromagnetic flowmeter and ERT to measure gas/liquid two-phase vertical slug flow is verified. By theoretical analysis, the relationship between the output of electromagnetic flowmeter and flow parameters is established. The electrical potential difference of the electromagnetic flowmeter, average velocity, volume flow rate and gas void fraction between the bubble size and location are also investigated. The fusion approach can be used to measure vertical slug flows.     

层流流量计的研究与应用

对脉动气流所作的理论分析说明,可以直接用于脉动气流测量的流量计必须具备两个条件：流速与所测参数之间应有线性关系,以及二次仪表应能反映出所测参数对时间的平均值。层流流量计就是靠由许多小流道构成的层流元件和在测压接头内装有阻尼元件来到这两条件的。文中讨论了层流元件的选型、流量计的设计方法以及层流元件加工等问题。雷诺数R e、R e与当量直径d d与元件长度l的比值的乘积R e·l/d d保持流速与测量段压差为线性关系的两个最重要的条件。文中并从理论上说明了获得层流量计的标准特性以及正确使用时的换算公式（30）和（31）式。所研制的D-100层流流量计,曾在195、295和395柴油机试验台上进行试验,在不用稳压箱的情况下,误差小于1～2%,从而证实了层流流量计直接用于测定脉动气流平均流量是简便而有效的。