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

[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