Principles of Electromagnetic Flowmeters

Introduction to Electromagnetic Flowmeter is a commonly used flow measurement instrument;

It is widely used in multiple fields to measure the flow rate of conductive fluids based on the induced electromotive force when the conductive fluid passes through an external magnetic field.

What are the advantages of electromagnetic flow meters?

Advantages of electromagnetic flow meters:

1. The sensor structure of the electromagnetic flowmeter is simple, and there are no movable parts inside the measuring tube, nor any throttling components that hinder fluid flow.

So when the fluid passes through the flow meter without causing any additional pressure loss, it is one of the flow meters with low operating energy consumption.

2. It can measure the flow rate of dirty media, corrosive media of seismic pressure gauges, and suspended liquid-solid two-phase flow.

This is because there are no obstructed flow components inside the instrument measuring tube, and only the inner lining and electrodes of the measuring tube are in contact with the measured fluid. The materials can be selected based on the properties of the measured fluid.

For example, using polytetrafluoroethylene or polytetrafluoroethylene as a lining can measure various corrosive media such as acids, alkalis, and salts;

The use of wear-resistant rubber as the lining is particularly suitable for measuring liquid-solid two-phase flows such as slurry and cement slurry with solid particles and high wear, as well as various suspended liquids with fibers and pulp.

3. Electromagnetic flowmeter is a volumetric flow measurement instrument that is not affected by the temperature, viscosity, density, or conductivity (within a certain range) of the measured medium during the measurement process.

Therefore, electromagnetic flow meters can be used to measure the flow rate of other conductive liquids after being calibrated with water.

4. The output of an electromagnetic flowmeter is only proportional to the average flow velocity of the measured medium, and is independent of the flow state under symmetric distribution (laminar or turbulent).

So the range of electromagnetic flow meters is extremely wide, with a measurement range of up to 100:1, and some even up to a operational flow range of 1000:1.

5. Electromagnetic flow meters have no mechanical inertia and are sensitive in response. They can measure instantaneous pulsating flow and flow in both directions.

6. The diameter range of industrial electromagnetic flow meters is extremely wide, with electric contact pressure gauges ranging from a few millimeters to several meters;