Measurement occupies a place in industrial production, in which flow measurement is an important part of measurement. Flow measurement is closely related to economy, national defense, education and scientific research. Measurement plays a vital role in the development of industrial production and scientific and technological research. Especially at the moment of energy depletion, the increasing level of industrial development and the rising trend of production automation, the position and role of the development and renewal of flowmeter in the development of economic production are becoming more and more important.
The research on the flow detection technology of fluid metering has been developed in industry for decades. The fluid metering and detection technology is progressing day by day, and the detection methods are becoming richer and richer. Among many measurement methods, non-contact measurement has become a hot spot in measurement and detection because the measurement probe will not be polluted by the contact measurement medium, Europe, America and other countries started early in gas detection and measurement, already have some mature gas detection and measurement instrument products, and have formulated relevant standards. In Asia, Japan and South Korea have also made good achievements in flow detection. Domestic research in this direction started late, but it has also made great development.
Flowmeter is one of the most representative instruments in industrial measurement. The development of flowmeter is accompanied by the development of society and industrial production. With the improvement of industrial production automation level, the accuracy and accuracy of flowmeter flow measurement need to be improved day by day, and the measurement range is becoming wider and wider. With the development of industrial demand and production, the flow measurement technology is also improving. In order to cope with the flow measurement for different purposes, different types of flow meters are constantly put on the market. There are no less than 100 types of flow meters in circulation in today’s market. However, so far, every fluid metering product on the market has its corresponding applicability and limitations. No flowmeter can be perfectly adapted to the accurate measurement of various conditions and fluids.
According to the measurement principle, the flow meters mainly include volumetric measurement flow meters and mass measurement flow meters. Because the volume of fluid will compress / expand under the influence of external environmental factors such as temperature and pressure. Therefore, when the temperature and pressure of the measured fluid change, the actual mass flow of the fluid will be affected by the parameters of the fluid medium (temperature, pressure, viscosity, etc.), which will cause the distortion of the measurement results. When the measurement result is distorted, it is necessary to convert the measured flow volume into the corresponding value under the standard state or specified state, that is, implement the corresponding temperature and pressure compensation. This flow volume conversion is widely used in temperature and pressure compensated flowmeter in industrial production. However, in the actual measurement process, when the measured fluid temperature and pressure begin to change frequently, it is difficult or even impossible to update the corresponding conversion at the same time. Therefore, the research and phase application of mass flowmeter begin to receive extensive attention.
Among them, the thermal gas mass flowmeter belongs to a kind of mass flowmeter, which is mainly used to detect the gas volume flow. The volume flow of the measured gas is obtained by conversion through the heat exchange relationship based on the heat transfer principle. At present, the thermal gas mass flowmeter actually used in the market can be divided into thermal distribution flowmeter for measuring low-speed gas flow (0.02-2m / s) and plug-in flowmeter for measuring medium and high-speed gas flow (1-100m / s).
Post time: 14-01-22