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Mark, my understanding is that the dishwashing soap does
indeed perform a function similar to water wetter in that it supposedly lowers
the surface tension/viscosity and permits the water molecules better contact
with the hot metal. The 10% antifreeze is for corrosion protection.
But presumable you could just use corrosion inhibitors which Red Line may have
in the solution.
But, since I feel comfortable with my current temp ranges,
I have not tried either Redline(recently) nor dishwashing
soap. I run around 20% antifreeze in the summer and bump it up to 50%
during the cold months.
Ed
----- Original Message -----
Sent: Monday, July 10, 2006 4:53 PM
Subject: [FlyRotary] FW: [FlyRotary] Re:
Suitability of NPG for Rotary Engine use
Jesse,
Here is a post from
Feb ‘06 by Lynn Hanover that I had filed away in my “Cooling” folder. It
addresses the issue of NPG, but his explanation of the “best you can do” is
right on, IMHO. Note his recommendation to use a teaspoon of dishwashing
soap. Could this have the same results as water wetter? Maybe so,
and for a few pennies. As I understand it, the 10% antifreeze is mainly
for corrosion control.
I saved a chart from
the other group that shows the heat transfer capacity of various ratios of
water and EG. 100% water is much better than a 50/50 mix. I’ll see
if I can find it and send it to you directly.
Mark
From:
Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Bulent Aliev
Sent: Thursday, February 02, 2006 7:00
AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Suitability of
NPG for Rotary Engine use
Lynn, what is the
purpose of the dishwashing soap?
The only reason for
using this stuff is to make the people selling it
happy.
I have never seen it
in a racing situation. Distilled water, maybe 10% antifreeze, a teaspoon full
of dishwashing soap. Put the 18-24 pound pressure cap on the make up tank. Get
the air out of the system and that is the best you can do. At 6,000 RPM the
stock pump will empty the coolant in 10 seconds or less.
If it won't cool
with the above setup, it isn't the setup. Its airflow/exchanger size/
distribution.
All bets are off for
turbo installations.
On cool days we run
a 160 degree thermostat and tape off part of the radiator (Griffin).
Normally, (up to the
hottest days) no thermostat, full radiator. Top temp is 180. Oil is 190.
It takes a big oil
radiator to cool a rotary. I have three 13 row
Setrabs.
If you watch the
movies of the instruments after a race, you would think the engine must be
junk. Not the case at all. Even an early downshift that takes the engine right
past the rev limit
(the drivers other
hobby) of 9,600 RPM has no affect at all.
I have yet to see an
aircraft installation that looked like it could put out more than 200
HP.
The two GM cores are
enough for water. Oil is a poor transfer medium so it takes a bigger cooler to
do the same job (remove the same number of BTUs per second).
There is just no
magic involved. There is no need to reinvent the wheel for each
installation.
If you have cooling
problems at 180 HP, how will you ever enjoy a 200 HP installation?
The HP is the easy
part. Get the cooling right first.
Just my
opinion,............I could be wrong.
Are there any
opinions on a good airfoil for 2,400 pounds going 200
MPH?
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