Engine performance/ Fuel energy figures sought

Jan 23, 2004 6 Replies

Hi All, following a conversation with a work associate concerning the improvement in engine efficiency over the years, I realised how little hard data I had at my disposal.



Does anyone know of any internet site where I can find the typical calorific values of petrol and diesel and typical efficiency figures for i/c engines. The only figure I can quote is 31% efficiency for a Petter Atomic in the Petter Oil Engines Catalogue reprint.



I'm not sure whether petrol or diesel has the higher calorific value and therefore don't know whether diesel engines give more mpg for this reason or because the higher compression ratio that diesel allows gives a more through burn of the fuel.



Regards, Arthur G


Hi Art, Here's one for you to ponder:

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=-=-=-=-=-=-=-=-= Rob Skinner La Habra, California

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================================================== And one more

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Mike.H.

my two cents worth; the quote from penn state university seems strange. for gasoline (petrol)they quote 8600 btu/gallon...and i'm assuming a US gallon, that's about 6 lbs/gallon. that would indicate about 1466 btu/lb. that's patently incorrect. . methanol has a btu/lb approximately 8600. i'm under the impression that gasoline is about 15,000 btu/lb.

aside, i use a gasoline burn of about 0.45#/hp-hr and 0.37#/hp-hr. i use 13.07 cu. ft. of air equals one pound. (for my calculations) am i off somewhere? i'd also be interested in a site on the interenet to go deeper into it. my best to a great newsgroup. sammmm

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Looks to me like there is a zero missing - 14,660 ?

Regards,

Kim Siddorn

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Mike.H.

Thanks, all for your input, I had previously found some info on the net, though some was contradictory!

Keep it coming, I won't have time to review the latest sites until after I come back from the pub. I expect all the statistics will seem very clear then! :-)

Thanks and Regards, Arthur G

Feeling thirsty already!

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