07/25/2003

Hartman's Fuels and Lubricants Book

A blend of gasoline, 25% toluene, 10% acetone ( to make it blend ) and 10%
nitromethane give a test octane of Research 99.9 Motor 75.4 R+M/2 of 87.2

Page 95 of drivia.

Looks like 10 to 20 percent by volume addition of Model boat fuel should not
cause issues.

Same section of Pharteman shows some promise for :
Methyl Acetate
Ethyl Acetate
n-Propyl Acetate
p-Amyl Acetate
Bomyl Acetate
Ethyl Butyrate
Butyl Benzoate
Diethyl Carbonate

All of which will take the octane above 100.

I like:
aniline
N-Methyl Aniline
Diethyl amine

And probably unobtainium
Isopropylbenzene ( cumene )
n-Problybenzene

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Hartman Page 75 on nitro-methane.  ( There really is usable data if you hold
your nose).   Next I need to find a way to get ahold of BYU and find out how
to get copies of their data!!!!!  Any academic whiz-kids around with a clue
how?  

( And I'd kill for a nice source for nitro-benzene at some rational price for
use as a fuel. )

"In 1985 Bush, Germane and Hess tested engines with nitromethane fuel combined
with methanal and various higher-carbon nitroparaffinic co-solvents. These
tests, at BYU, investigated various engine operating parameters on power
output and combustion severity, including combustion ratio, ignition timing,
air-fuel mixture, and co-solvent effects.

Testing a 5:1 compression engine with 30 degrees spark advance at slightly
over 1000 rpm at stoichiometric mixtures showed that increasing nitromethane
fuel from zero to 50 percent in methanol increased power by roughly 45%, while
knock increased roughly 20%.  Using a 40 percent nitromethane mixture, both
maximum power and maximum knock occurred at 20 degrees BTDC and dropped
quickly with increased or decreased spark advance.  Since knock fell off more
rapidly than power on the retarded side of peak power, Bush et al recommended
setting spark slightly retarded of peak power to control knock while
maximizing power.

Increasing compression ratio from 5:1 to 8:1 increased both power and knock,
but power increased faster.  Changing mixture strength revealed that power
increases steadily while knock decreases rich of 1.1 equivalence ratio all the
way to 1.7 and beyond.  In the final testing, when replacing the methanal
co-solvent with a nitroethane or nitropropane fuel, power increased with
increased percentages of nitromethane ( equivalence ratio was constant, so the
air-fuel ratio became more fuel rich as the nitromethane percentage increased
) and knock severity decreased with increased nitromethane.  This is opposite
to the observed results with the methanal co-solvent, in which knock
increased.  It required 50 percent more nitromethane in methanal to achieve
power levels equal to nitromethane and nitroethane, and at that level the
knock was 50% greater than with the pure nitropaffifin blend.  The
experimenters speculated that this effect was due to a change in composition
or temperature of the end gas, since no other engine conditions were changed.
Nitropropane appeared to be a more effective co-solvent than nitroethane.  The
researchers tried adding gasoline -type TEL and MMT antiknock additives but
found them ineffective at reducing knock, while hurting power slightly.

It is interesting to consider the affect of gasoline as a co-solvent in these
tests, since the decreased oxygen content of nitropropane compared to
nitroethane seemed to produce results ...."

Same page on part of why I like nitro.

"Stoichiometric combustion of nitromethane yields 5.82 moles of product for
4.57 moles of intake charge reactants, a favorable ratio of 127 percent
compared to methanal and gasoline's 106 percent.  Dissociation - in which
molecules split into simpler molecules or individual atoms under high
temperatures and pressures-increases nitromethane's product to reactants ratio
to 130%, and with very rich mixtures ( half stoichiometric ) increases it to
160 percent, partially due to the appearance of carbon monoxide."


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Tracked the report down.  Its still on the shelfs at BYU - but not able to get
to a phone call till monday.  This material desperately needed for fangle
base.

Thesis (M.S.)--Brigham Young University. Dept. of Mechanical Engineering

Improved nitromethane utilization in spark-ignition engines 

Bush, K.C.

They have the original in the Harold B Lee special collection and a
circulating copy.

Nobody is close ( I think ) but if it was possible to find a way to get a
copy, I'll be selling senoritas che che's muey granda's bunns to get a copy.
Rosaritos - Great for restying your hair!