There is good thought here. I hope that my comments are not out of date
already because my ISP "fixed" his unbroken system last night and now he has
everyone's email jugged up in his server. Oh, well..
If I may throw in a few comments, interspersed...
> Well not working from a schooled mind here, but rather from common
> sense...
Yikes! Is this normal? Having a schooled mind is contrary to common sense? I
like to think I have both (but my wife might debate on that...)
It would seem that in the atomization of the fuel a significant
> amount of heat would be lost therefore negating any positive mileage
effect
> of heating it. Additionally, that heat would be lost to the airstream
which
> is not going to be of any advantage for power either.
If I understood the thought...where is the heat lost from? Isn't a separate
heating source used to bring the fuel to a vaporized state? Now, given the
vapor state, fuel is evaporated at 100 percent at approximately 120 deg F
(16:1 fuel air) then can it be cooled to the point where droplets form in a
manifold with air temperatures exceeding that? I dunno. But in a
supercharged (turbo or otherwise) the air temps are much higher. Should it
be possible then vaporized fuel could form droplets and this would have the
effect of removing heat from the air? That would mmake for a denser charge
air and more power. How much? Beats me! But I am willing to bet a dollar to
a donut that vaporizing fuel before the carb or hell even after in the
manifold wont make much difference. I think I can remember when this heating
of fuel made the rounds here and nobody bit. Lots of smoke but no real
flame.
It seems (at least to
> me) that in and of itself heating the fuel and/or air does offer slight
> advantages in one direction (mileage) at the cost of the power and visa
> versa. Is the gain worth the cost???
You might be able to make the fuel a tad more combustible ond or make it a
tad less dense so that the measuring device (carb) does not give it the full
measure of heat to the combustion chamber (ie make it lean) and hence give a
bit more milage. But the potential cost? Detonation and broken parts. It
takes a well designed motor, I think Bob, pointed out to make use of this.
Running your daily beater really lean by heating the fuel might give you
reason to visit the mechanic to his advantage.
> Just like air fuel ratios there is optimal and going richer or leaner
> only offers a slight adavantage depending on whether you are looking for
> mileage or power.
Well said!
Thus, with the exception of a turbo (or supercharged) car
> that generates excessive heat cooling or heating the fuel and or air is
like
> the "taste great, less filling argument." It is both and neither.
Well, no. Under no circumstance can I think of a situation where I would
want to heat the air. On my turbo'd car, I want to cool the air as much as
possible and in fact get it below ambient if possible (water air
intercooler). This allows for greater mass of air into the combustion
chamber and when mixed at the proper F/A ratio give best power and or
mileage, depending on your tune.
> To put this issue back into perspective the initial question regarded
> vaporization of the fuel as opposed to the typical atomization. I
therefore
> would pose three questions to that:
>
> 1. I understand that fuel is heated to a vapor. Assuming that a standard
> butterfly valve is used to control air flow how would one control the
actual
> fuel ratio. It seemed that a pool of fuel is heated to provide the vapor.
I
> also assume that to either be constant, or at least unable to respond to
> instantanious changes in air supply. Thus, how in this system is air fuel
> ratio maintained with throttle input variation?
Great Question!! I can think of at least one scenario. Let the carb do it's
work in metering the proper fuel amount to the air flowing through the
venturi. Then heat that mixture to the point of full fuel vaporization. As I
mentioned earlier in the post, that does not have to be a really high temp.
But you would need some kind of mixing device to assure that it all was
brought to the vaporization temperature. When the car is switched off, no
offensive smells. All trapped or used. I suspect that there are other
strategies that might work also.
>
> 2. Once the vapor enters the cooler airstream is it possible that it
would
> condense and negate the advantages of being a vapor?
Well, remember that the air is usually pretty warm by the time it get to the
manifold. That is why companies sell cold air kits...to help lower that
charge air temp. And this is a good question because those of us in colder
climes would not benefit from this at all! Because it (the gasoline) would
condense out and plate the runner walls in the manifold.
>
> 3. Just how oderous would this be in a real world application. Imagine the
> aroma of this still heated fuel long after the engine has been shut off
(can
> you say "fuel porcolation"). The enviromentalist would have an ozone layer
> meltdown (so to speak).
Yup. Nobody like the smell of unburned gasoline. But I think it could be
done without these side "benefits". But as you said before, Why? And for
sure we don't need additional ozone losses or laws to restrict our driving
privileges.
>
> It seem that this is a "drawing board" issue that can quickly turn into a
> dog chasing it's tail.
Nah, heck, we call this bench racing! This is where a lot of good stuff
comes from. As long as nobody gets mad or angry that his pet ox has been
gored, it is all in good fun and maybe, just maybe, enlightenment.
>
> Tom Witt B9470101
Tom, I enjoyed your posting! Keep it up!
>
>
Mayf, the red necked ignorant desert rat in Pahrump and where the hell is
Push, NV anyway?
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