Electronic – Acoustic Measurement of water level


Is it possible to measure the amount of water in a rubber water tank by using sound waves?

I want to make a non intrusive measuring device that attaches to the outside of a tank, and is able to approximate the amount of water in the tank however I don't know how to calculate what sound of a specific frequency will "sound" like given different mediums (e.g. sound travels faster in water than air).

Best Answer

Also consider using a capacitive sensor.

If you glue two plates side-by-side on the outside of the tank, they will act as a capacitor with the water (or air) in the tank as the dielectric. Because water has a dielectric constant that is 100x that of air, you can easily and accurately relate the capacity of the plates to the water level in the tank.

See Measuring Water Level Without Getting Wet for more information.