marc mularz wrote:

 Hello all:
 Well its been two weeks of the iron nail sitting in water/ glycol mixtures
 and here are the results.
 A.  The iron nail in pure distilled water (redundant) is severely corroded.
 This began within SIX hours of being placed in the test tube !!!  As I
 expected, its not the ions in the water that cause the corrosion, it's the
 oxygen dissolved in the water.

 B.  The nails placed in the water glycol mixtures show no corrosion that is
 visible to the un-aided eye, even in as low as a 10 % solution.  I was
 suprised that this low concentration of anti-freeze contained this degree of
 anti-corrosive properties.

 >From this, I would think that those who want to run a lower than
50/50 ratio
 of water/glycol would only have to be concerned with the freezing and
 boiling characteristics of their mixture.  OTOH I don't believe that a
 difference of 0.12 in the specific heats of pure water vs. 50/50 is
 significant in terms of the heat that must be removed by the cooling system.
   Hope this info helps.
 Take care, Marc M

Alfonso Lebron-Berges wrote:

Regarding the lack of oxidation at low concentrations of glycol, I
guess you conducted this test at room/ambient temperatures. Remember
that a chemical reaction, and oxidation is one, accelerates
significantly with the increase of temperature. I would be concerned
about using 90% water (10% x-glycol) in an environment with much
higher temps. than that present while you conducted this test. At
least until proven otherwise.

Alfonso Lebron-Berges

The AirCraft Rotary Engine NewsLetter.              Powered by Linux.

http://home.earthlink.net/~rotaryeng/            http://www.linux.org