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I read today that next seasons F1 engines will have the same thermal efficiency as a modern diesel engine, I think I sort of know what this means but I wouldn't mind a proper explanation from the people you know.
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Maybe it means the heater won't work for the first 5 miles;-)
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Efficiency is usually defined as output as a percentage of input, so in this case the usable kinetic energy achieved relative to the chemical energy in the fuel.
But if you're only going to give it a couple of outings a week...
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So they go from 5% to 15% efficient.
IIRC correctly from my physics lectures you can't achieve more than about 20% efficient from any engine unless you drastically increase the operating temperature. Though I may be making that up.
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it means they will all fail after 100 miles with DMF failures.
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Why does the thermal efficiency matter in a racing car?
You have a choice of engine A, which requires you to carry X weight of fuel to last the required number of circuits, and engine B, which requires Y weight of fuel.
Engine A + fuel weighs W1
Engine B + fuel weighs W2
Then compare power outputs per weight of engine +fuel.
Does it follow that the more thermally-efficient engine makes the car go faster?
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I got the impression that it was trying to imply that F1 cars are getting closer to road cars in terms of their 'green' credentials.
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>> I got the impression that it was trying to imply that F1 cars are getting
>> closer to road cars in terms of their 'green' credentials.
You might be right, but...
Thermodynamics was my nemesis as an engineering student; I'm not sure why they have picked out thermal efficiency rather than overall efficiency.
However - F1 engines have some factors in their favour.
- they presumably have relatively high compression ratios (though not as high as diesels, which accounts partly for the greater efficiency of the latter)
- they operate much of the time at full load (or no/negative load) and high rpm which is intrinsically more efficient and also means fewer compromises need be made in design than would be the case if other characteristics has to be catered for with equal importance.
- they are not as far as I know burdened with some of the efficiency leeching environmental requirements of ordinary car engines.
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Engine tech explanation needed - Manatee
