Flow sensing (Doppler) "outside" the pipe - anyone did it before?

[flotulopex]

Hello,

I'm looking for quite a while around some "usable" information about the Doppler effect in application with water flow measurement. Haven't got much luck until now

Does anyone know about this system, meaning measuring water flow from "outside" the pipe involving, for instance, ultrasonic sensors...and that doesn't come up to a cost of thousands of $? These systems look to be "sealed" in some kind of secret defense for any reason I don't know.

Purpose: I'm working in an industrial air-conditioned environment and I need to manage energy. Now, I measure temperatures and calculate energy upon the chilled water pumps theoretical flow capacity. It could be possible to install mechanical flow meters; they are quite cheap but also somehow fragile. Unfortunately, the pipe works to instal the mechanical flow meters has not been accepted (too difficult to stop the cooling).

Thank you for any info.

[wdmagic]

here is a good link to more info on what your wanting to do, scroll down about halfway, I have only seen stuff done with thermal mass flow meters, and venturi meters. but his page has some formulas and such that may help.

LINK

[flotulopex]

Yup, I googled that one already.

It would be nice to have some "practical" info, schematics or experience from someone.

[LinkMTech]

I read about this sometime ago where the water flow sound was measured using a mic at various flows to get a reasonable flow rate measurement but can't recall the published paper.
I did find this simple project using a piezo transducer and an Arduino. Though written in C, the build directions are spelled out so it can be converted to PBP.

[wdmagic]

http://www.instructables.com/id/Low-...bient-Display/ hehe I had that one too...

http://www.usbr.gov/pmts/hydraulics_...P/PAP-0838.pdf

http://books.google.com/books?id=yH7...page&q&f=false

http://ny.water.usgs.gov/pubs/jrn/ny...02-r38200b.pdf

http://www.science.uva.nl/remotelabs...riments/VU/LDA

[flotulopex]

Well... doesn't look that simple :-(

Thanks a lot for the links :-)

Going to do some testing....