atomization enhancement

[Howard Wilkinson]

James:
    I'm firmly in your camp.......Statements recently made about
Cummins and other engines are absurd.  Either someone is mixing up
decimal points or mistaking bar for PSI.  I can speak from experience
with Cummins common rail systems when I say that they are nowhere
close to these numbers (I've guaged them).  Also The injector pop
pressures of most diesel engines I've worked with would make me think
that someone is mistaking bar and psi pressures.  1500 psi would be a
reasonable breaking pressure for a typical injector, and 4k-5k psi
would be a very high pressure injector.  I believe that Cummins B
series and C series engines (not common rail) operate in the latter
range.... don't quote me here as I have only hearsay numbers on these.
There is no way on God's earth that a CAV, Roosamaster, or Stanadyne
rotary pump can produce the pressures people have been throwing about,
and I have grave doubts that any of the piston pumps can do this
either.  There is no doubt that diesels develop more power with better
atomization, and run more efficiently.... as do gas engines...this has
long been known, but pressures of 20,000 psi are not only difficult to
achieve, but EXTREMELY DANGEROUS.  The only safe way to achieve these
kind of pressures safely would be to do it with an injector which did
the pumping so that there was no danger of line breakage.
    We are being deluged with bad information here, but unfortunately
I have no way of convincingly refuting it.  In my opinion it's utter
nonsense!!    H.W.

-----Original Message-----
From: James Montebello <jamesm at talarian.com>
To: diy_efi at efi332.eng.ohio-state.edu
<diy_efi at efi332.eng.ohio-state.edu>
Date: Wednesday, May 05, 1999 12:37 PM
Subject: RE: atomization enhancement


>> I just looked this up. All the new german diesel engines use
>> common-rail
>> (BMW, Audi, Mercedes) and uses a pressures of approx 1350 bar.
>> VW has a new diesel at 1.9 liter that uses one separate diesel
>> pump/cyilinder and uses a pressure of 2050 bar. According to all
these
>> manufacturers the higher the pressure the better the combustion.
>
>1350 BAR!?!  2050 BAR?!?
>
>20,000psi and 30,000 psi?  Tell me there's a missing decimal
>point, or a units mistake here. 13.5 and 20.5 bar sound more
>believable.
>
>james montebello
>