From: "Charlie England ceengland7@gmail.com" <flyrotary@lancaironline.net>
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Date: Fri, 4 Mar 2022 13:10:19 -0600
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Subject: Re: [FlyRotary] Renesis coolant flow measurements
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On 3/4/2022 11:43 AM, Finn Lassen finn.lassen@verizon.net wrote:
> Got my "Save a Drop" water meter in the mail yesterday. Unfortunately 
> it only shows accumulated flows and no gal/minute mode. That means I 
> could not insert them in the running engine system to measure flow 
> rate there.
>
> Claims +/- 1.3% at 6 gal/min, 70 psi and 68 deg F. Max pressure 116 
> psi. (Sounds like there is a rotating "wheel" inside when water flows.)
>
> So I did two one-minute runs that gave 18.1 and 18.5 gal/min (varies 
> by pump pressure as you can see from the calibration spreadsheet). But 
> the calculated flow rate in the spreadsheet (in zip file) comes out to 
> about 16 gal/min average.
>
> For some reason the 0.807" ID homemade flow sensors (with 1/16" OD 
> pitot and static tubes) appear to produce lower pressures than 
> predicted by the formula referenced in earlier recent posts. I 
> calibrated the differential pressure sensors I use (MPX10) with a 
> water manometer, so I'm fairly sure that my measured inches of H2O 
> (head?) pressures are accurate within a couple percent.
>
> That means that the Renesis total flow (see the other attached 
> spreadsheet) could be as much as 12% higher or 53 gal/min at 4,800 
> engine RPM.
>
> Again, I have two radiators in parallel, with as low as 1/2" ID 
> restrictions in fittings and welded tubes.
>
> Calibrations were done with pure water. Engine (system) runs with 
> 50/50 antifreeze. At running temps (180+ F) the specific heat 
> difference should be about 12% (only changing the 0.186 to 0.203 in 
> the spreadsheet formulas).
>
> What I don't know and hope one of the experts here (Steve Boese) can 
> clarify is if zero system pressure (calibration flow of water emptying 
> into the air) vs system pressure (varies with RPM and temps; couple of 
> psi to as much as 8 psi in some of the runs) in the engine runs would 
> make a difference.
>
> In any case I'm now fairly sure that coolant flow rate and flow 
> balance between the two rads is not a factor in my cooling issues.
>
> Finn
Any particular reason for staying with 50/50 mix? Most of the antifreeze 
mfgrs seem to say that around 1/3 antifreeze is enough for corrosion 
protection, so you'd get slight improvement in heat carrying ability 
from the coolant. If you live where it rarely gets colder than around 
0*F, the charts look like 30-35% is more than adequate. IIRC, Lynn H has 
talked about running pure water with a few drops of detergent 
functioning as 'water wetter'.

I'm having a bit of an 'oldtimers' moment, but I have a vague memory 
about closed loop pumping systems being more efficient in flow, but as I 
said, the memory is pretty fuzzy.

Charlie

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