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What are the reasons why electromagnetic flowmeters are not suitable for measuring gases?

The electromagnetic flowmeter is a volume flow measuring instrument. During the measurement process, it is not affected by the temperature, viscosity and density of the measured medium (in a certain range). Therefore, the electromagnetic flowmeter can be used to measure the flow rate of other conductive liquids only after being calibrated by water. The output of the electromagnetic flowmeter is only proportional to the average flow velocity of the measured medium, regardless of the flow state (laminar or turbulent flow) under a symmetric distribution. Therefore, the electromagnetic flowmeter has an extremely wide measuring range, and its measuring range can reach 100:1, and some even reach a running flow range of 1000:1.

Electromagnetic Flowmeter
This is mainly because of the inherent shortcomings of the electromagnetic flowmeter, that is, the shortcomings are determined. Let us analyze the reasons. Electromagnetic flowmeters are mainly inadequate: they cannot be used to measure gases, vapors, and liquids containing large amounts of gas. It cannot be used to measure liquid media with very low conductivity. For example, for petroleum products or organic solvents, electromagnetic flowmeters are currently unable to do anything.
Analysis of the reason why electromagnetic flowmeter can not measure gas
1. The electromagnetic flowmeter has no mechanical inertia and is sensitive to the reaction. It can measure the instantaneous pulsating flow, and can also measure the flow in both directions. Industrial electromagnetic flowmeters have a wide range of diameters from a few millimeters up to several meters, and there are already 3 millimeters of real-flow calibration equipment in China, which lays the foundation for the application and development of electromagnetic flowmeters.
2. The sensor of the electromagnetic flowmeter has a simple structure, and there are no movable parts in the measuring tube, and there are no throttling parts that hinder the fluid flow. Therefore, when the fluid passes through the flowmeter, it does not cause any additional pressure loss, and is one of the flowmeters with the lowest energy consumption in the flowmeter. It can measure the flow rate of smear medium, corrosive medium and suspended liquid-solid two-phase flow. This is due to the fact that there is no obstructive flow component inside the metering tube. Only the measuring tube lining and the electrode are in contact with the fluid to be measured, and the material can be selected according to the nature of the fluid to be measured. For example, polytrifluoroethylene or polytetrafluoroethylene can be used as a lining to measure corrosive media such as various acids, alkalis, and salts. The use of wear-resistant rubber as the inner liner is particularly suitable for measuring wear with solid particles. Larger slurry, cement slurry and other liquid-solid two-phase flow and various suspended liquids such as fiber liquid and pulp.

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