Tom Tweed wrote:
>
> Hello Joe,
>
> in regard to the EGR lowering combustion temperature, IF I recall
> some decades-old chemistry correctly, the reason has to do with
> the air / fuel mix being exothermic, or heat-producing.
>
> Normally the fuel mix has air (oxygen 20% by volume) enough to
> `burn' more or less completely, and since the carb mix has been s
> set to optimize power (heat) output with `normal' air, adding
> oxygen-depleted exhaust into the mixture has the effect of lowering
> the heat output, since there is less free O2 available to react in
> relation to a mix using 100% outside air.
>
> Since gases don't have enough mass to hold much in the way of
> latent heat, the fact that hot exhaust gas is used is less impor-
> tant than the drop in the efficiency of the exothermic reaction.
>
> Hope this helps, and hope I'm correct !
>
> Any `real' chemists, not synthetic ones, please correct as necessary.
>
> Best regards,
> Tom Tweed
> GC-MS lab technician, Wright State U. Chem. dept.
> SW Ohio
GO TOM!!!!!
Man, do I LOVE this mailing list!
John
|