08/24/2003

CO Monitoring

Thanks - I am trying to run down a methodology of continuously monitoring
engine exhaust to determine the lowest level of HC and CO - balancing that
against a wideband for point retrieval, and looking for a sudden sharp upturn.

This upturn point corresponds to the point were combustion is failing, and in
conjunction with an EGT, can be used to limit where you want to run in a lean
burn situation.

And, if I don't like lean burn, CO can be used to track and return richer than
stoic combustion.  Useless old NACA papers being the basis for every author
including Heywood on the percentages of H2, CO, HC, CO2 etc.

One very nice feature of CO is that it burns about 400c hotter than normal
hydrocarbons and has an extremely high auto-ignition temperature.  Also,
approximately 2/3's the energy release of oxidizing C ==> CO2 is from CO ==>
CO2.  And CO combustion virtually stops around 1000 kelvin.

CO will not burn in absolutely pure O2 no matter what - but, even a few
molecules of water, combined with any form of ignition, and it burns fast hot
and well.  Needs the hydroxide radical to start combustion and the radicals
get reused to the end.