Among the flow meter instruments, the metal tube variable area flow meter is a very frequently used instrument. Metal tube variable area flow meters are often used for measurement in various industries, such as petroleum, chemical, water treatment, and other complex and harsh environmental conditions.
Metal tube variable area flow meter is a traditional variable cross-section flow meter, which has many advantages such as simple structure, reliable operation, small and stable pressure loss, and can measure low flow rate media. It is widely used in measuring high temperature, high pressure, and corrosive fluids. medium. As determined by the measurement principle of the metal tube flow meter, it generally needs to be installed vertically. However, in some specific industrial applications, it is necessary to use a horizontally installed rotameter. Although the measurement principle is the same as the classic vertical rotameter, It is a rotameter with a special structure that can be installed in horizontal pipelines.
Metal tube variable area flow meter is used to continuously measure the volume flow of liquid and gas in closed pipelines. It has a solid and reliable structure and can adapt to flow measurement on various occasions. The metal tube variable area flow meter has the advantages of a simple structure, small pressure loss, large flow range, reliable operation, and convenient maintenance. It is widely used in flow detection and process control in national defense, petroleum, chemical industry, metallurgy, electric power, medicine, energy, and other industrial sectors.
Working principle of metal tube variable area flow meter
The metal tube variable area flow meter is composed of two parts. One of the rotameters is a tapered tube, which gradually expands from bottom to top. The other part of the rotameter is a float, which is installed in the tapered tube and can be free to move up and down along the centerline of the tube. When the metal rotameter is in use, when the flow of the measuring medium is measured, the measured fluid flows in from the lower end of the tapered tube, and the flow of the fluid impacts the rotor. At this time, it will generate a force (the magnitude of this force varies with the flow rate). When the flow rate is large enough, the generated force can hold up the rotor and make it rise. The measured medium flows through the annular section between the rotor and the tapered tube wall at the same time and flows out from the upper end. When the measured medium flows, the force on the rotor is exactly equal to the weight of the rotor in the fluid (called the displayed weight). The float is in a balanced state under force and stays at a certain height. Through this analysis, it can be explained that the height of the position of the rotor in the conical tube has a corresponding relationship with the flow rate of the passing medium. Finally, by observing the position height of the rotor in the conical tube, the corresponding medium flow value can be obtained.
Method of improving design efficiency of metal tube flow meter
The overall design and research of the metal tube variable area flow meter, according to the previous Bernoulli equation, the equation requires that the fluid motion is a constant flow, and the fluid is an ideal fluid (ideal fluid refers to a fluid that ignores viscosity) and is incompressible Homogeneous fluid, but the fluid flowing through the rotameter does not strictly meet these three conditions. The design of traditional flow meters requires experiments to check and modify the design drawings, which not only prolongs the design cycle but also increases the design cost. In order to solve the above two reasons, computational fluid dynamics is introduced into the design of metal rotameters. Then numerically simulate the flow field of the float flow sensor, and evaluate the preliminary sample design by comparing the simulated and experimental data, so as to optimize the structural parameters of the flow sensor and make the design of the flow sensor more reasonable, thereby greatly improving the design efficiency and further solve the problem. sisco metal tube variable area flowmeter has a solid and simple structure, long service life, reliable operation, and can adapt to flow measurement in various complicated occasions.