atomization enhancement

[Bruce Plecan]

I was wondering about now if that many folks could make the same error,
well, I'll let it be now.
Thanks Brock
Bruce


> >     I find that number hard to believe if my conversion figure is
> > correct 1 bar = 14.5 PSI (rounded).  26100 PSI........  You won't
> > catch me working around one of those systems... a leak could easily be
> > fatal!     It that the system on Caterpillar I've heard about where a
> > cracked line can cut put out a fuel stream that will cut steel.
> >     The Ford "Powerstroke" I've been told is a single rail system
> > which has an oil pressure driven injector which is computer triggered.
> > An extra oil pump supplies pressure to the injectors which use the oil
> > pressure to create high injection pressures.  I've never worked on the
> > power stroke..... only the old 6.9 & 7.2 engines which used an
> > ordinary rotary pump.  New injectors for the Powerstroke are $500.00
> > each according to the local Ford people.... I suppose $4k for a set of
> > injectors isn't so bad if you can afford a $40K pickup.
>
> Ahhh...  It's a special day when the efi hot-rod discussion group starts
> talking about Diesel combustion and fuel systems.
>
> You CAN believe your ears here, folks.  Common rail (this is what it's
> usually called, rather than "single rail") fuel systems can go as high as
> 1800 BAR (yes, that's around 26,500 psi!).  An analogy was drawn by
somebody
> else to the typical gasoline fuel injection system on most automobiles,
and
> yes, it's the same idea.
>
> The extremely high pressures are commonly generated by a piston pump
running
> at engine speed.  And, as you guessed, the lines and rail have to be very
> beefy material.  These injectors aren't cheap.  Imagine an injector
> (typically 4-8 holes) that can withstand that pressure, and still react
> quicker than an automotive fuel injector.
>
> I've often wondered what would happen if you tried to squirt gasoline at
> these pressures.  I'm not enough of a chemistry type to know how gasoline

> reacts at extremely high pressures.
>
> Even the lowest pressure Diesel systems used today have roughly 600 BAR
> operating pressures.
>
> Other designs you may have seen are "unit injectors" or "unit pumps".
Unit
> injectors are either hydraulically assisted and electronically actuated
> (HEUI) or they are cam assisted and electronically actuated (EUI).  Either
> way, the fuel is pressurized right at the injector as opposed to the
common
> rail that has a supply pump that is commonly gear driven off the gear
drive.
> Unit pumps are individual pumps, one for each cylinder, that are cam
driven.
> It's much like EUI, but the pump is seperate from the injector and
connected
> by a line.
>
> I'm sure that's more than you wanted to know about modern Diesel fuel
> systems.  Now somebody try to postulate what would happen if you used one
of
> these with gasoline...
>
> I'm a high-speed gas engine fan (at heart), but some days I can't help but
> smile when I see 850 lb-ft of torque at 1300 RPM out of 6.4L on 30 pounds
of
> boost.  Heck, 280HP at 2300RPM is no slouch, either.
>
> -Brock
>
>