X-Mozilla-Keys:                                                                                 
Bill Freeman wrote:

Paul Y -

 I have never seen a big version of a fuel flowmeter or nat gas meter
 (i.e. positive displacements or turbine types) for instrumentation, but I
assume
that they must exist somewhere.  With a variable speed pump drive
and inlet and outlet pressure gages, thermometer, plus a trashcan on a
large capacity scale and a large source of inlet water, you can do * part*
of the mapping.  The problem is going to be the part where the inlet
pressure is positive, as I assume is likely to be the case in an actual
motor.  Is the inlet at lower than atmospheric pressure on an automotive
water pump??  I am not an expert on liquid pumps, but assume that the
inlet pressure should  have a significant effect on performance, such
as cavitation.

So, a simple open - bucket to bucket system will get a portion of the
curve, you really need a sealed system and a flowmeter to do the
whole map, and the bucket to bucket may only provide the map in
areas of non-interest.

Since you need  to recirc the water and keep from heating it up due to
pumping heating, so you need a cooler.  Why not an engine on a dyno
with a side loop in the water pump outlet to permit throttling the outlet?
Then on to a radiator, etc.  Could actually be on any engine stand,
including on an
A/C (prop off for safety?) with a externalized 'breadboard' cooling system.
Car rad, cooling fan, pressure and temp gages plus a flowmeter.

Any reason why a home made venturi with a pair of taps and a delta P
gage plus some calibration work can't do what we need?  Seems like
a reasonable home project and can be calibrated by the open bucket
gravityflow onto a scale method.  Start the flow into a trash can on
a large dial or digital scale.  Get system stabilized, start stopwatch at
a convenient measure like passing thru 35 lbs, record the delta P on
the venturi, and flow temp, then stop stopwatch on some other convenient
measure, like passing thru 100 lbs.

No rocket science here.  A good set of runs may require pressure flow, like
from the city water system, and might get a bit exciting trying to find a
big enough spigot ( fire hyrrant?? :-)   for some of the higher flow rates.

Take care.

Bill

 
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