Pressure Sensors & ION Eyes

[goflo at pacbell.net]

Hi Garfield

I'll be taking you up on the speed controller assistance. Thanks.
Need to decide whether to go with what I've got or just build a 
bench from scratch. I'm taken with this Paxton blower notion -
Really sounds like a winner. A/C motor controls are outside my
hack so I'm all ears for your scheme.

Lemme run this by you: Re pitot tubes - How 'bout sensing "static"
pressure in a duct of known dimension and velocity with a pitot 
tube. If you know both then flow is straightforward computation.
High quality pitot tubes are relatively cheap (Dwyer). A range of 
duct diameters is possible if necessary. Comment?
 
Not to beat accuracy/repeatability to death, but I've found in 
component testing that what you've got hung on the piece under test 
(manifold, air straightener, whatever) makes way more than a couple
of per cent difference - I doubt it'll surprise you that a lot of the
"big" numbers you hear about are obtained with very "unrealistic" test 
set-ups, to put it kindly.
I once had the honor of being abused by Ken Sperrling (Air Flow
Research) for having the temerity to test one of his creations (for a
customer), creating a certain amount of heartburn thereby. We all got
over it, but the point is that hokey data and flow bench are synonyms
unless you're determined ...

Hope this is of some use.

Jack