Hi Charlie,
All my pumps, but the Facet, are on the
forward face of the Firewall, so can’t help you there.
Regarding “T” the Facet pump, Pressure
will generally overwhelm volume, you can think of a large mass of slow moving
fluid as being effectively a stationary pool of liquid (taking it to the extreme
of no motion), so a higher pressure fluid would simply squirt into the larger
volume liquid similar to as it if were a large tank). Yes, if the larger mass
were moving at a much higher velocity, it might in effect offer a shearing
force across the opening to the facet pump and have detrimental effect
(possibly) – but I doubt you are going to have that kind of fluid
velocity in your return line.
Ed
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Charlie England
Sent: Thursday, June 03, 2010 5:22
PM
To: Rotary
motors in aircraft
Subject: [FlyRotary] high/low
pressure pumps question
Have any of you RV-x builders considered
putting your pumps on the aft side of the spar, to keep the cabin & engine
compartment 'clean'? It looks like it would be possible, by using the existing
holes for wire in the center section (RV-7). If not, are you just putting them
under the center cover between the seats & raising it up a bit?
Also, how about running the transfer
(Facet) pump's output line T-d into the main pump's return line? There should
be minimal pressure, but will the high pressure pump's much larger volume
overwhelm the modest Facet transfer pump? (Or, maybe venturi effect would
eliminate the need for a Facet....)