If a fuel mixture can be represented by the general formula CxH2x, prove that the stoichiometric gravimetric air/fuel ratio is 14.8:1.
The combustion reaction for a given fuel mixture will look as follows:
CxH2x + 1.5x(O2 + 3.76N2) → xCO2 + xH2O + 1.5x*3.76N2 The molar ratio is 1.5x:1, to find the gravimetric ratio, the masses of the air and fuel should be found. This can be done by multiplying molar ratio with molar weights of the fuel and air. m(fuel) = 12*x + 2x*1 = 14x m(air) = 1.5x(16*2 + 3.76*14*2) = 1.5x*137.28 = 205.92x The gravimetric stoichiometric air/fuel ratio then is 205.92x:14x = 14.71:1 The dry exhaust gas analysis from an ...
