08/26/2003

Keith Duckworth is in error - and his conclusions are totally meaningless.

RON octane is determined at very low rpm.

Engine peak octane demand is between 4500 -6000 rpm depending on depending on.

Honda F-1 engines, well documented, ran at 12000 and Honda published
information that the actual octane needed at that rpm was around 50 - even
straight diesel would not detonate.

In fact, in the operating region of the Honda Engine, the F-1 fuels high
octane not only was not needed, but slowed the flame development and greatly
hindered power.

The addition of n-heptane - octane of ZERO - sped up the combustion to
increase the pressure and power generated by the fuel - because the fuel did
not burn fast enough for the engines rpm.

But - now I will be trashed for calling Duckworth an idiot - even though all I
am saying is he is sadly lacking in chemistry of fuels.  But no one pays him
to do so and the fuel blending people have forgot more since the late time
they slept than Ducksworth will ever know about FUEL.

So be it and screw it.



On Tue, 26 Aug 2003 05:58:47 -0500, you wrote:

> >CD&T Jan 92
> >- Keith Duckworth said the chemical specs and fuel tables in many
> >chemistry
> >  books were apparently in error, at least about their applications as
> >motor
> >  fuels.
> >- some fuels that fared poorly in RON knock tests actually worked very
> >well
> >  in F1 racing engines
> >- "once you start blending fuels, the results defy logic if you try to
> >predict
> >  their behavior from the listed characteristics of the components." 
> >(seems
> >  he doesn't understand chemistry - dw)
> >- "Some of the ethers like MTBE can be useful - TAME may be better
> >because it
> >  has a specific energy appreciably higher and contains less oxygen so
> >you can
> >  blend in more of it before you run up against the [F1] 2% oxygen
> >limit"
> >- in 1988 Honda's F1 cars used 84% toluene, diluted by 16% n-heptane to
> >  reduce the RON number from 120 to 102
> >- the RON is measured by US CFR standard, ASTM D2699.  The test engine
> >runs
> >  at 600 RPM with 52 deg C inlet temp.
> >- fuel           blending RON  stoich  specific     % oxygen
> >                                      energy mj/kg  by weight
> >  typical petrol   90-98        14.6    2.92            0
> >  butane           99           15.4    2.96            0
> >  n-heptane        0            15.2    2.92            0
> >  iso-octane       100          15.1    2.93            0
> >  benzene          100          13.3    3.03            0
> >  toluene          120          13.5    3.03            0
> >  methanol         115-130      6.5     3.08            49.9
> >  ethanol          112-120      9.0     3.00            34.7
> >  MTBE (1)         115-123      11.7    3.00            18.2
> >  TAME (2)         111-116      11.9    3.17            15.7
> >  nitromethane        -         1.7     6.60            52.5
> >
> >        (1) methyl tertiary butyl ether
> >        (2) tertiary amyl methyl ether