ATI Supercharging

[Darrell Norquay]

Steve wrote:

> Sorry, i'm new here but isn't that backwards? Lean is much hotter than rich!
> (So - rich causes the fuel to ignite in the CAT - BAD, Lean causes it to MELT
> BAAAAD!).
> 

I'm not all that familiar with catcons, but I am pretty sure that they are
used solely for reduction of unburned hydrocarbons and combustible products
in the exhaust.  After all, a catalyst by definition enhances or causes a
chemical reaction to proceed faster, or initiates a reaction under conditions
which it would not normally occur.  Logic dictates that if you are running 
lean, there would be less combustible by-products, and the catcon would not
have "fuel" to react with, thus the internal temperature of the catcon would
be lower.  (Jeez, I sound like Spock there :)  If, however, you run rich, the 
catcon has an abundance of fuel, which would cause it to overheat and fuse 
it's internals.  Some catcons have an auxiliary air input from the AIR system 
pump to provide additional oxygen to help combust unburned fuel, which would 
help to raise their internal temperature even more under rich conditions.

I think this is a separate issue to exhaust gas temperature, which is 
generally higher under lean burning conditions, and lower with rich.  The 
catcon is capable of GENERATING heat greater than the incoming EGT if it 
has fuel to react with.  If you were running lean, EGT would be higher, but 
heat generated in the catcon would be lower, and vice versa.  IMHO, the 
change in exhaust gas temperature due to rich or lean would be much less 
than the change in catcon internal temperature under the same conditions.

Come on all you combustion engineers, am I on track here?

regards
dn

--

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 Darrell A. Norquay              Internet: dn at dlogtech.cuc.ab.ca     
 Datalog Technology Inc.         Voice: (403) 243-2220
 Calgary, Alberta, Canada        Fax:   (403) 243-2872            
 
       "Absolutum Obsoletum" - If it works, it's obsolete    
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