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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. 相似文献
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Korneev R. A. Tukhvatullin A. R. Fafurin V. A. Shchelchkov A. V. 《Measurement Techniques》2019,62(4):347-353
Measurement Techniques - A new approach to the assessment of interfering factors that arise in the process of diversion of a flow of liquid in the weighing device of a calibration device is... 相似文献
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Gerasimov A. P. Ivanov V. P. Krasavin V. M. Lakhov V. M. Rainchik S. V. Semenova O. K. 《Measurement Techniques》2005,48(4):374-380
A mathematical model of the flow of a gas in Laval nozzles is analyzed. The model is used to obtain equations for measuring the mass and volume flow rates of a gas.__________Translated from Izmeritel’naya Tekhnika, No. 4, pp. 44–48, April, 2005. 相似文献
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Tony Grift 《Particulate Science and Technology》2003,21(2):177-193
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. 相似文献
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TONY GRIFT 《Particulate Science and Technology》2013,31(2):177-193
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. 相似文献
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本文使用新建立的水流量标准装置,依据JJG 1038-2008《科里奥利质量流量计检定规程》,采用静态质量法,对科里奥利质量流量计示值误差测得值的不确定度进行分析。 相似文献
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A method is developed for determining the mass discharge and consistency of a pipe flow carrying a suspension under pressure. Mass discharge and consistency are determined by using readings of the power used by the hydraulic dredger which moves the flow. 相似文献
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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. 相似文献
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科氏质量流量计模拟驱动方法研究 总被引:1,自引:0,他引:1
驱动系统是科里奥利质量流量计的重要组成部分之一。它为流量管提供驱动力,使流量管以其固有频率和稳定的振幅振动,并且能够跟随流量管固有频率的变化而变化。目前的驱动系统是基于模拟信号的工作方式。分析了这种驱动系统的工作原理,比较了各种波形的驱动信号,研究了几种驱动电路。 相似文献
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金属雾化过程气体质量流率的研究 总被引:1,自引:0,他引:1
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。 相似文献
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Journal of Engineering Physics and Thermophysics - This article considers mathematical simulation of heat and mass transfer processes in the course of SHF heating of flow of a viscous fluid, oil... 相似文献
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We continue our solid 4He flow experiments in which we grow solid helium samples at constant temperature in the hcp region of the phase diagram. We exploit the properties of liquid helium in a confined geometry (porous Vycor glass), and induce a mass flow through the solid at pressures higher than the bulk melting pressure. We previously observed flow, but our temperature was limited to T≥350 mK. At T≈400 mK it was found that the flow ceased at P≈27 bar, and no flow was observed for T>550 mK. We have begun to extend our measurements to lower temperatures, and our data show that at lower temperatures we observe flow at higher pressures. 相似文献