TI Ultrasonic Sensor - Liquid Identification and Concentration

RE: TI Ultrasonic Sensor - Liquid Identification and Concentration

dubbie — Wed, 16 Oct 2019 09:13:22 GMT

This was very interesting. I have previously read about using ultrasonics to measure fluid characteristics but never seen it put so easily into practice. It was also interesting to see the 'speed' varying when the fluid is agitated as well.

Dubbie

RE: TI Ultrasonic Sensor - Liquid Identification and Concentration

uludag2806 — Tue, 15 Oct 2019 11:56:54 GMT

Hi Jan;

Have you faced a problem "The VI is not executable. The full development version of LabVIEW is required to fix the errors"

RE: TI Ultrasonic Sensor - Liquid Identification and Concentration

jc2048 — Wed, 30 Dec 2015 19:46:36 GMT

As it stands, I'm not sure I'd call it a "real world" application (the measurement of small concentrations of detergent in water).

To make it useful you'd need an accurate measurement of the water temperature too, wouldn't you?

It works with your experiment because you start by measuring the speed with pure water and then add the other material quickly enough that you can assume that there hasn't been much change in the water temperature. (If the temperature of the water has stabilised, that is. If the tap water has just come out of the tap and is heating towards ambient, then the stirring will probably account for at least some of the change you're seeing.) But for an absolute measurement - not a before and after differential one - you'd need a temperature reading too.

The temperature measurement would need to be pretty accurate: the change you see in the speed (1.1m/s) is equivalent to approx a half degree C change in temperature (if I've worked it out right).

If you put one of the equations from the following document into a spreadsheet you'll be able to see the range of values for the speed as temperature varies:

http://resource.npl.co.uk/acoustics/techguides/soundpurewater/speedpw.pdf

RE: TI Ultrasonic Sensor - Liquid Identification and Concentration

DAB — Sun, 27 Dec 2015 22:36:48 GMT

Very nice post on using science to verify speed of sound in a liquid.

DAB