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I've researched this product thoroughly and used to do fluid heat transfer
experiments in my occupation. If you drained all the fluid in your radiator,
replaced it with 100% antifreeze (normal ethylene glycol) you'd have identical
boiling point and heat transfer characteristics to Evans product. So you could
operate zero pressure, as it wouldn't boil over until it reached 392F.
Unfortunately both Evans and 100% glycol have very low heat transfer
coefficient (.66). They are both insulators, so all things being equal, you have
to increase your radiator area by 30% to achieve the same engine operating
temperature. Compared to running with 30% glycol mix, that's quite a penalty.
Ethylene glycol is substantially superior to Evans, as you can tune it's
efficiency by adding water. For example, it you decide to operate with more
efficient 50/50 mix, the heat transfer coefficient jumps from .66 to .86. You
get to reduce your radiator size a lot, yet still have 230F boiling point.
Evans has a great propaganda web site, a lot of people get sucked in. It's
one of those rare products that has zero redeeming value. Far inferior to
glycol. Yet I bet it will continue to sell for decades.
-al wick
----- Original Message -----
Sent: Thursday, October 10, 2013 11:15
AM
Subject: [FlyRotary] Re: waterless
coolant?
You might want to check what happens to the viscosity of this fluid at
lower temperatures. Its been a while, but as I recall this fluid
turns into heavy syrup at lower temps. You can visualize your water pump
churning (cavitating) in a void of this fluid at low temperatures while
not moving any through your cooling system.
The fluid next to the rotors would undoubtedly get hot -while that
in the radiator and water pump may act as a (Temporary) plug to coolant flow –
until the heated fluid explosively forces the issue.
I tried finding the viscosity charts they used to have on the site, but
could not find it.
My impression when I looked into this fluid back a few years ago, was
that this heavy viscosity at low temps was probably not much of a draw
back compared to the benefits in a racing motor – heated garage, summer
temps, etc. But, might be a different story for aircraft
application.
Ed
Edward L.
Anderson
Anderson Electronic Enterprises LLC
305 Reefton
Road
Weddington, NC
28104
http://www.andersonee.com
http://www.eicommander.com
Sent: Thursday, October 10, 2013 1:05 PM
Subject: [FlyRotary] Re: waterless coolant?
This
appears interesting. I looked at the website and was unable to find the
heat capacity of the fluid. The higher boiling temp may not be helpful
if the heat capacity is such that you need a large delta T to transfer the
same amount of heat as a water-based system.
One
must also consider the effect of the higher operating temperature on engine
oils. At some temperature, oil loses its lubrication ability. I
don’t know what that temp is but assume it is different for different
oils. Just because the coolant allows higher operating temperatures,
doesn’t mean one should do that.
Gordon
C. Alling, Jr., PE
President
acumen
Engineering/Analysis,
Inc.
540-786-2200
www.acumen-ea.com
From: Rotary motors in
aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Michael
Silvius
Sent: Thursday, October 10, 2013 1:19 PM
To:
Rotary motors in aircraft
Subject: [FlyRotary] waterless
coolant?
While on the subject of
cooling, I am curious if anyone has tried the waterless coolant? Seems to
offer some advantages, namely higher boiling boint and low pressure, is there
any reason it should not be used in our
aplication?
No virus found in this
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Database: 3222/6738 - Release Date:
10/10/13
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