How to Measure Flow with Magnets - (Magnetic Flow Meters)

What happens when a civil engineer mixes water and electricity? The results aren't always ideal, but you always learn something!

A magnetic flow meter relies on Faraday's Law of Induction to measure the flow of a fluid. Magnets outside the pipe create a magnetic field. Electrodes are located perpendicular to the magnets. A conductive fluid moving through the pipe will generate a voltage (electromotive force) between the electrodes due to Faraday’s law. The faster the fluid moves through the pipe, the higher the voltage. Once you know the velocity of the fluid, you can calculate flow using the cross sectional area of the pipe. In this video, I walk through some of the details that electrical engineers have worked out so that this ingenious device can work properly. Unfortunately I couldn't get it working very well myself!

Want to learn more?
Wikipedia - https://en.wikipedia.org/wiki/Magnetic_flow_meter
Neha Girme Blog - https://nehagirme.wordpress.com/2011/11/19/electromagnetic-flowmeter-design/
Arudino Code - https://github.com/gradyh/dc_pulse_gen

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Website: http://practical.engineering
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3D Model: Devin Sloan
Music: Elexive - Tonic and Energy (https://www.youtube.com/watch?v=U6fBPdu8w9U)

Errata:
-At 4:36, the signal to noise ratio is low, not high.