peterrr
07-14-2014, 03:33 PM
I have done some thinking and figured out how anti knock works:
The burning of gasoline is an exponential accelerating process. When you have an ideal mix the speed is greatest. When you miss the ideal mix by 10 % the reaction will slow down by 10 %. The reaction is regulated by condensing fuel onto the cylinder head. Here you see that you get a regulating loop over reaction, pressure, condensation, reaction speed, etc. The gain in this loop is only 1. Normally you will get a linear rise in pressure, but if you enter the condensing zone while the piston goes up you will get a quadratic curve. The substances creating knocking control convert a vast majority of the fuel into large molecules. After the detonation a lot of gooey fuel has to be burned off the cylinder head, with air with little oxigen in it. Result: soot ,unburnt HC.:mad: Adding water vapour would make the engine run cooler and the burn off easier
The burning of gasoline is an exponential accelerating process. When you have an ideal mix the speed is greatest. When you miss the ideal mix by 10 % the reaction will slow down by 10 %. The reaction is regulated by condensing fuel onto the cylinder head. Here you see that you get a regulating loop over reaction, pressure, condensation, reaction speed, etc. The gain in this loop is only 1. Normally you will get a linear rise in pressure, but if you enter the condensing zone while the piston goes up you will get a quadratic curve. The substances creating knocking control convert a vast majority of the fuel into large molecules. After the detonation a lot of gooey fuel has to be burned off the cylinder head, with air with little oxigen in it. Result: soot ,unburnt HC.:mad: Adding water vapour would make the engine run cooler and the burn off easier