Re: GAS-L: Internal Combustion with Producer Gas

[Reedtb2@cs.com]

Dear Peter et al:

Duh.  You said :

 Obviously there is an ignition problem with just "spark". The diesel
 principle is injection of a fuel into an atmosphere heated to the flash
 point of that fuel with enough oxygen present to accomplish combustion.

WRONG WRONG!  No problem with "spark", except the trouble of converting.  The 
trouble with not converting is (1) you continue to use 20% diesel and (2) you 
are always tempted to trash the gasifier and use pure diesel.  If you convert 
to spark you'll be OK.

Maybe my earlier message was unclear.  The reason the producer gas doesn';t 
ignite in pressure ignition is that it has a very high octane - and a very 
low cetane number.  Ergo, you can use spark ignition or pilot diesel.  

 Lots of labs are now using "spark converted diesel" engines.  See Prof. 
Parikh/Shashikantha excellent paper at recent ASME meeting based on SHshi's 8 
year thesis.  Can you post Mrs. P?  

                ~~~~


>Pure hydrogen is far richer than producer gas with all that nitrogen.

Wrong.  Pure hydrogen contains 300 Btu/scf and producer gas is typically 150 
Btu/scf.  Not "far" richer, but a factor of two for sure.  

FUel injection is of course out of the question, since compressing the weak 
producer gas - or the hydrogen (unless at tank pressure) would be 
prohibitively expensive.

                                            ~~~~~~~

This is a major "mechanical" adaptation. I simple wonder why compression
must be lowered when running producer gas only -- when it does not need to
be when running a small amount of diesel??

Probably doesn't need to be reduced, due to the reduced charge, even at the 
high CR.  BUt I hope we hear form Prof. P. on why she thinks 11-3 CR is 
optimum.  

I presume one can add an extra head gasket to reduce CR?

YOurs truly,       TOM REED
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