涡轮流量计对流体流量的计量

本介绍用较准确度的涡轮流量计构成的较高准确的度计量系统以及计量系统不确定度的合成方法，列出了确定了流量系数的计算公式。     

间接式质量流量测量中的技术问题

化工生产管理中的经济核算，生产过程中的物料平衡以及贸易、运输过程中的计量，最终都是以质量来进杆核算的。故准确地测量介质的质量流量是非常重要的，本文介绍了间接式质量流量测量中的一些技术问题。     

科氏力质量流量计质量流量参量的温度系数

科氏力质量流量计的质量流量和密度参量的温度系数 ,与其材料的线膨胀系数和杨氏模量的温度系数有关 ,并可由谐振频率的温度系数求出。当采用 1Cr18Ni9Ti时 ,在 - 10℃～ 6 0℃的温度范围内 ,质量流量参数的温度系数是 - 4 2 4× 10 - 4 ℃ ,密度参数的温度系数是 4 2 4× 10 - 4 ℃。     

质量流量计在烟草加香流量控制中的应用

江苏省徐州卷烟厂在“九五”技改工程中采用了许多新技术，其中，制丝线香料厨房因采用科氏质量流量计进行控制。使烟丝的香精香料掺兑准确度得到了很大提高，对稳定卷烟产品的内在质量起到了重要作用。     

科氏质量流量计测量含气液体流量关键技术综述

含气液体流量测量是科氏质量流量计面临的测量难题,对科氏质量流量计的驱动技术、信号处理技术都提出更高的要求.从驱动、信号处理、误差修正这3大核心技术出发对科氏质量流量计测量含气液体流量进行综述,分析含气液体流量下,驱动、信号处理以及误差修正技术的难点,并针对难点总结出含气液体流量下最佳的驱动技术、信号处理技术和误差修正技...     

基于“双流量”测量法的气体质量流量计的研究

为了准确测量气体质量流量,排除气体密度变化带来的影响,提出双流量测量法原理。通过理论分析和试验,证明DF型涡轮质量流量计在测量气体质量流量时,不受密度变化的影响,而且可以动态测量气体密度。     

用临界流流量计测量大气中空气质量流量的湿度修正

介绍了用临界流流量计测量大气中空气质量流量的两种湿度修正方法,并做了简单的分析和比较。     

气体流量计分界流量划分推荐

根据现有的气体流量计标准和规程,在流量传感器或流量计产品的计量性能技术要求中,多数涉及到分界流量。由于流量范围内低区和高区的最大允许误差要求不同,所以,分界流量在各流量计的标准或规程中均有规定,但这些标准和规程中的要求存在不同程度的差别,不一致。分界流量属于人为的划分,其目的是为了扩大流量计的范围度,同时又不让最小流量偏离线性区太远。为使流量计的分界流量有相同的划分标准,同时,也为促进流量计产品的计量性能的提高,特推荐流量计分界流量从准确度和范围度两方面加以规定。     

质量流量计在油品计量中的应用

本文对质量流量计在油品计量中的应用谈了几点体会：做好质量流量计的选型是关键；进行必要的温压补偿，压力补偿有在线压力补偿、固定压力补偿二种方法；正确的安装是保证质量流量计正常使用的关键；定时进行流量计标定。     

State Primary Standard of the Unit of Liquid Mass Flow Rate

The pressing current problems of increasing the level of the metrological service of instruments for measuring liquid mass flow rate are presented. The action principle, metrological characteristics, results of investigations of the State primary standard of the unit of liquid mass flow rate, and the verification scheme regulating the order of transferring the size of the unit to working measurement standards are presented.     

金属雾化过程气体质量流率的研究

金属雾化过程中颗粒的尺寸大小及统计分布规律是影响粉末冶金和喷射沉积快速凝固材料组织和性能的关键因素。雾化气体的质量流率对金属颗粒的尺寸及分布有很大影响，本文根据热力学第一定律推导出雾化气体质量流率的表达式，气体质量流率主要受雾化器出口面积及气体膨胀比的影响，出口面积愈大，膨胀比愈小，气体质量流率愈大，当临界膨胀比（Ｐ２／Ｐ１）ｃ＝时，气体质量流率达到最大值。     

Fundamental Mass Flow Measurement of Solid Particles

A generic mass flow measurement device was developed as a variation on the theme of counting. In a hypothetical infinitely sparse mass flow, the number of passing particles could be counted in a time frame and multiplied by the mean mass per particle to obtain a mass flow per time unit. In a mass flow of realistic density, however, particles travel in cluster formation and direct counting of individual particles is impossible. If a method could be available that reconstructs the original number of particles in a cluster, the mass flow can be computed for realistic clustered mass flows. This reconstruction algorithm was developed in this research; it uses the measured cluster lengths to reconstruct the total number of particles in each passing cluster. The lengths of the clusters were measured with an optoelectronic device. The reconstruction algorithm was developed using simulation, augmented by clustering theory. For identical diameter particle flow, simulation results showed that the number of particles in a cluster could be reconstructed using a very simple reconstruction formula. This formula uses only the total number of clusters per time frame and the total number of individual particles measured in the same time frame. However, identical diameter flow is not realistic, since even identical particles are measured with a certain error. Reconstruction of the realistic distributed diameter particle flow was approximated using the identical particle method. The optical mass flow sensor has major advantages over traditional methods. It is virtually insensitive to vibrations, contamination, temperature drift, and misalignment and the underlying measurement concept is well understood. But most importantly, the sensor does not require calibration. The mass flow of identical particles (4.5 mm air gun pellets) was measured with an error smaller than 3% even for high density flow rates.     

Fundamental Mass Flow Measurement of Solid Particles

A generic mass flow measurement device was developed as a variation on the theme of counting. In a hypothetical infinitely sparse mass flow, the number of passing particles could be counted in a time frame and multiplied by the mean mass per particle to obtain a mass flow per time unit. In a mass flow of realistic density, however, particles travel in cluster formation and direct counting of individual particles is impossible. If a method could be available that reconstructs the original number of particles in a cluster, the mass flow can be computed for realistic clustered mass flows. This reconstruction algorithm was developed in this research; it uses the measured cluster lengths to reconstruct the total number of particles in each passing cluster. The lengths of the clusters were measured with an optoelectronic device. The reconstruction algorithm was developed using simulation, augmented by clustering theory. For identical diameter particle flow, simulation results showed that the number of particles in a cluster could be reconstructed using a very simple reconstruction formula. This formula uses only the total number of clusters per time frame and the total number of individual particles measured in the same time frame. However, identical diameter flow is not realistic, since even identical particles are measured with a certain error. Reconstruction of the realistic distributed diameter particle flow was approximated using the identical particle method. The optical mass flow sensor has major advantages over traditional methods. It is virtually insensitive to vibrations, contamination, temperature drift, and misalignment and the underlying measurement concept is well understood. But most importantly, the sensor does not require calibration. The mass flow of identical particles (4.5 mm air gun pellets) was measured with an error smaller than 3% even for high density flow rates.     

Method of Measuring the Mass Flow Rate of a Substance by Using Restricting Apertures

A new method is considered for measuring the mass flow rate of a substance in pipelines using restricting apertures, without the use of instruments for measuring the density and temperature of the flow. A structural measurement scheme is given and analytical expressions are obtained for determining the mass flow rate and the density of the substance under working conditions. A calculation is given of the errors of the flow parameters.     

科里奥利质量流量计的原理及应用

文章主要介绍科里奥利质量流量计的原理和应用,并举例说明。     

基于分子流传感元件的真空腔体漏率测量方法

本文介绍了一种基于分子流传感元件的真空腔体漏率测量方法,该方法通过分子流传感元件测量真空腔体整体漏率,采用的测量装置由气体流量测量系统、真空抽气系统、恒温系统等部分组成。在测量系统中,流经传感元件的气流处于分子流状态,通过测量传感元件两端的差压,计算质量流量,可以得到真空腔体的整体漏率。实验中对多个真空腔体漏率的测量结果表明,该方法可以实现对10^-5-10^-3 Pa·m³/s量级真空腔体漏率的准确测量。除去本底漏率之后,测量结果与理论结果高度拟合,测量结果显示最小偏差为0.05%,最大仅为0.62%。且通过改变分子流传感元件流导值和差压变送器量程可以进一步扩展该方法可测真空腔体整体漏率范围。     

科里奥利原理在测量散粒料流量中的应用

介绍了利用科里奥利原理测量固体物料流量的方法,以及实现这个原理的典型测量装置———科氏质量流量计。为了使测量达到较高精度,必须解决两个关键问题:力矩的精确测量和转速恒定。文中对科式质量流量计和其他测量系统(如冲板系统、溜槽系统)进行比较,指出其特点为测量精度不受物料特性(颗粒度、容重)影响,并且可以锁住逆向空气流,不用添加锁风装置。利用科氏质量流量计测量固体散料、粉体只要物料不凝聚和粘着,量程范围可达1～150t/h,测量精度优于1%。