流量测量领域中的新技术

流量测量领域中的新技术北京化工大学自动化系孙延祚一、电磁流量计的无水干标装置电磁流量计属于非接触式流量测量仪表，它有许多优点，因此应用日益广泛。电磁流量计成功的发展在很大程度上取决于仪表的计量保证手段，即水流量校验装置的状况。采用仿真模拟方法实现各种...     

流量检测仪表 第一讲 流量测量的一般概念

在工业自动化仪表中,流量检测仪表以其种类繁多、影响因素复杂而著称。为普及流量检测仪表知识,为沟通用户和制造厂之间的信息,我们特请本刊编委邵朋诚高级工程师撰写《流量检测仪表专题讲座》。该讲座重点介绍国内普遍使用和即将推广使用的流量检测仪表,计划分12讲: 1.流量测量的一般概念;2.流量测量仪表的分类与选用;3.节流式流量测量装置;4.容积式流量计;5.涡轮流量计;6.电磁流量计;7.漩涡流量计;8.浮子(转子)流量计;9.插入式(分流式)流量测量方法;10.超声波流量计;11.质量流量计;12.流量测量仪表的发展动态。     

基于MATLAB外啮合齿轮流量计的流量特性仿真研究

分析了普通外啮合齿轮流量计的瞬态流量,由齿轮马达的瞬态流量特性推导出了流量计的瞬态流量数学模型,给出了不同齿数情况下流量计的流量脉动,研究了脉动率和齿轮齿数的关系,利用MATLAB软件模拟了流量计的流量特性仿真曲线,证明了可以用适当增大从动轮齿数的方法来降低流量计的流量脉动。     

浅谈应变靶式流量计的使用

靶式流量计测量高粘度介质流量有其独特的优点,传统的靶式流量计存在机械结构复杂、灵敏度低、量程范围窄等缺点。新型应变靶式流量计由于采用了新技术,所以结构简单、灵敏度高。本文着重介绍了应变靶式流量计的工作原理、安装调试要求以及常见故障和处理方法。     

智能流量仪表与批量控制

１流量特性对流量计的要求１．１流量特性决定了选用流量计的动作原理在化学反应生产过程中,为了对生产进行指导、控制,流量仪表的使用是必不可少的。根据生产工艺复杂程度的不同,生产要求的各不相同,使用流量仪表的种类也各不相同。在某助剂生产过程中,我们也使用了...     

浮子流量计流量方程的改进与试验研究

针对现有浮子流量计流量方程在理论推导过程中存在的问题,重新推导了浮子流量计流量方程,得到改进的浮子流量计流量方程。根据试验数据比较了经典浮子流量计流量方程与改进的浮子流量计流量方程的α-Re特征曲线,通过对两个浮子流量方程的比较和分析,解释了以往浮子流量计流量方程推导中存在的概念混淆问题。最后指出改进的浮子流量计流量方程与经典浮子流量计流量方程在本质上是相同的。     

温压补偿型超声气体质量流量计

对超声时差法进行算法改进后，结合气体密度公式推导出超声质量流量方程，据此设计出温压补偿型超声气体质量流量计，给出了流量计核心系统及温压补偿部分的硬件设计。将只用于流体体积流量测量的超声流量计推广到气体质量流量测量领域，使超声流量计趋向理想化。经实验证明此流量计在测量常压空气时精度可达1．42％。     

相似理论与流量系数

0 前言 本文根据相似理论对孔板流量计、浮子流量计、旋涡流量计的流量系数进行了分析推论,这种分析方法也适于分析类似工作原理的其它流量计的流量系数。     

艾默生高准带增强型MVD^TM技术的ELITE科氏流量计荣获2006年工控网“创新产品用户奖”

近日在“2006年第五届中国工控网年度评选”中，艾默生高准公司推出的具有新一代MVD^TM技术的ELITE流量计获得用户最多投票数，最终捧得“创新产品用户奖”。拥有新技术的高准ELITE科氏流量计不但达到了行业一流的质量和流量精度水平，并且密度精度也提高1倍。这意味着该技术也设立了科氏测量精度新的工业标准。     

流量测量关注点和动向

1951年毕业于大同大学（上海）电机系,原上海光华仪表厂总工程师,教授级高级工程师。长期从事流量仪表研究开发和生产技术等方面工作,现任中国仪器仪表行业协会流量专业委员会顾问。曾发表论文80余篇,获专利两项,所编著、主编《流量测量方法和仪表的选用》、《流量计应用指南电磁流量计》、《新型流量检测仪表》、《流量测量技术及仪表》于近年出版。     

差压流量计在饱和蒸汽测量中的应用

介绍全新插入式差压流量计威力巴(Verabar)的测量原理及应用。具体介绍威力巴流量计的选择，威力巴的压损效益，配套的变送器及显示仪表的选择和量程设定，与孔板相比具有结构简单，安装快捷，维护方便，测量准确，范围宽等特点。     

Experimental research of single-hole and multi-hole orifice gas flow meters

As energy efficiency is becoming more important today due to limited energy resources as well as their rising prices and environment issues, it is crucial to have reliable measurement data of different fluids in production processes. Because of its simplicity, affordability and reliability, orifice flow meters are again becoming subject of numerous researches. Conventional single-hole orifice (SHO) flow meter has many advantages but also some disadvantages like higher pressure drop, slower pressure recovery, lower discharge coefficient etc. Some of these disadvantages can be overcame by multi-hole orifice (MHO) flow meter while still maintaining advantages of conventional SHO meter. Both SHO and MHO flow meters with same β ratios were experimentally tested and compared. Results showed better (lower) singular pressure loss coefficient and lower pressure drop in favour of the MHO flow meter. Experimental data indicates that MHO flow meter is superior to the conventional orifice flow meter, but further research is necessary to make the MHO a drop-in replacement for a SHO flow meter.     

"V"型内锥式流量计的应用前景

长期以来,标准孔板由于其发展技术成熟、标准化程度高、结构简单等特点在过热蒸汽流量计量中得到非常广泛的应用.然而,孔板流量计存在着一些固有的缺陷,如流出系数不稳定、线形差、重复性不高、准确度受客观因素制约而无法达到设计要求、量程比小、压损大等.本文介绍"V"型内锥式差压流量计的工作原理,分析了如何解决孔板流量计的这些缺陷,并通过计算实例介绍"V"型内锥式流量计在节能方面的优点,最后介绍在恶劣条件下"V"型内锥式流量计是如何提供准确计量的.     

Multiphase flow measurements using coupled slotted orifice plate and swirl flow meter

Multiphase flow metering is a major focus for oil and gas industries. The performance of a modified version of a close coupled slotted orifice plate and swirl flow meter for multiphase flow was evaluated to provide further development of a new type of multiphase flow meter. The slotted orifice provides well homogenized flow for several pipe diameters downstream of the plate. This characteristic provides a homogeneous mixture at the inlet of the swirl meter for a wide range of gas volume fractions (GVF) and flow rates. In order to evaluate the performance of the designed flow-meter, its response was investigated for varying pressures and water flow rates. The proper correlations were established to provide high accurate two-phase flow measurements. The new proposed approach provides the GVF measurement with less than ±0.63% uncertainty for GVF range from 60% to 95%.     

Performance evaluation of Coriolis mass flow meter in laminar flow regime

In many fluid flow applications, mass flow rate is preferred over volume flow rate, as it is more beneficial in terms of cost and material balance calculations. Coriolis mass flow meter (CMFM) is accepted widely for mass flow measurement owing to its accuracy and reliability. However, it has been found to under-read the mass flow rate in laminar flow region [1], thus limiting its application in this region. The secondary flow in the curved tube section influences the generated Coriolis force and leads to a deviation in meter readings. Commercial CMFMs are available with various curved tube configurations and need to be analyzed for their application in laminar region. This paper presents comprehensive experimental and numerical investigations performed to evaluate the influence of tube configuration and other meter parameters, such as drive frequency, amplitude of vibration, and sensor position, on the performance of the CMFM in laminar region. The findings of this study have put forth a suitable combination of tube configuration, drive frequency, and sensor position while using the CMFM in laminar flow regime.     

Novel mass air flow meter for automobile industry based on thermal flow microsensor. II. Flow meter,test procedures and results

A prototype of mass air flow meter for automobile industry was developed on the basis of thermal flow microsensor. Design and manufacturing technology of the flow meter are described. Test procedure and results are presented. Developed prototype of flow meter can diagnose gas flow rates in a wide range.     

大管径热式气体质量流量计在烧结生产中的应用

本文主要介绍了大管径插入式热式气体质量流量计的特点、工作原理及安装和使用.本文对大管径插入式热式气体质量流量计与孔板式差压流量计的性能指标也作了详细的比较.     

In-situ calibration of permanent magnet flow meters in PFBR using noise analysis technique

In Fast Breeder Reactor sodium circuits, permanent magnet flow meters (PMFM) are extensively used to measure the liquid sodium flow rate. The performance of PMFM can degrade with respect to time due to various reasons. This degradation results in reduction in output voltage and affects flow meter stability. The distortion of the magnetic field in the large diameter flow meters makes its characteristics nonlinear. Further, the performance of the flow meter is also affected by vibrations, shocks, temperature and change of reluctance within the magnetic circuit. Hence, it is desirable to calibrate the PMFM at periodic time intervals for ensuring accuracy and stability. However, it is very difficult and almost impossible to calibrate large size flow meters once installed in the system under actual flow conditions in a sodium test loop. Therefore, it is necessary to calibrate the flow meter in-situ without disturbing its normal operating conditions.Experiments were carried out in different sodium loops in Fast Reactor Technology Group (FRTG) and Fast Breeder Test Reactor (FBTR) with permanent magnet flow meters of different sizes to develop an in-situ calibration procedure. Cross-correlation technique is studied and the flow rate is estimated from the transit time with a deviation of ±5.5%, which is comparable with that of calibration of the flow meter in actual sodium test loop. In this paper, in-situ calibration of PMFM is discussed with experimental details, data acquisition, cross-correlation technique and the results obtained.     

车载式液体流量计检定装置设计

液体流量计广泛应用于贸易结算和生产控制,属于强制检定的计量器具。传统液体流量计检定装置体积大,只能安装在固定场合。流量计送检给企业生产造成很大的影响。设计了一种车载式液体流量计检定装置,该装置可开展现场检定,对企业生产的影响小。     

科里奥利质量流量计发展及应用现状

简要回顾科里奥利质量流量计的发展过程,着重总结了其国内外发展情况及应用现状,并指出其发展趋势。