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FUEL FEED SYSTEM OF PETROL ENGINE

FUEL THERMOCHEMISTRY ::

We are trying to identify the chemistry behind the engineering of effficient, powerful automobile engines. In actuality, the early automotive engineers such as Charles Kettering, knew from their first trials that power and efficiency in an engine improved as the gas-air mixture was compressed to higher pressures at ignition. But as the engineers built higher compression ratios they began to hear unwelcome "knocking" caused by uneven gas-air combustion. The knocking reduced the power of the explosion and could damage the engine itself. Kettering and others, including Thomas Midgley considered alcohol as a complete replacement fuel for gasoline because it combusted at high compression without the knocking. But they also sought a low concentration fuel "antiknock" additive for gasoline.
Well, fundamental chemical principles do guide the designers. These principles are both limiting and enabling. Thermochemistry limits by showing that there is only so much energy is available for moving the car down the road. Thermodynamics enables by showing us how to maximize the energy available for doing the work of propulsion.