Subject:        High boiling point coolant.
   Date:        Thu, 07 May 1998 17:07:02 -0700
  

Some more info on Evans propylene glycol coolant (no water).
(EGW is eth. glycol water mix.)

-------------------------------- Water --- 50/50 EGW --- Evans
-------------------------------- @16 psi -- @16 psi ---- @0 psi
Boiling Point ---------- F ----- 252 ------ 268 --------- 369
Viscosity 212 F ------- cp ----- 0.28 ----- 0.7 --------- 2.35
Density 77 F --------- lbs/gal - 8.34 ----- 8.84 -------- 8.59
Specific Heat 212 F -- cal/g.K - 1.0 ------ 0.88 -------- 0.71
Heat of Vapor. ------- cal/mol - 9.7K ----- 9.8K ------- 12.5K
Vapor Press. 176 F ---- hPa ---- 490 ------ 400 --------- 11
Surface Tension 77 F --dyn/cm --- 72 ------- 56 --------- 36

Jack Evans also recommends upping the flow to 90 gal/min in a
small block running at 7,000 to 8,000 RPM because of the lower
specific heat. (This alone may be the main benefit.)

Special rads are needed to flow 90 gal per minute. He sells a
27.5 by 15 inch, two rows, 1.25 inch tubes with #4 AN fittings.
All rads have 18 fins per inch. Looks pretty good for an
aircraft. He also sells a 22 by 13 inch, two rows, one inch tubes
with auto hose fittings.

He claims his system and pumps pay off in terms of increased
gross HP out verses increased pump HP in.

He also calims that 220 to 240 F oil temp is optimum. (What
weight oil?)

They will send you reprints of a couple of articles including the
one I mentioned in High Tech Performance magazine if you ask.
Don't tell him you are going to run it in an aircraft.

http://www.evanscooling.com

Paul

 
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