1. The Theory of Combustion Benzene as a Fuel

3. Combustion Stoichiometry Air contains molecular nitrogen N 2 , when the products are low temperature the nitrogen is not significantly affected by the reaction, it is considered inert . The complete reaction of a general hydrocarbon C  H  with air is: The above equation defines the stoichiometric proportions of fuel and air. Example: For benzene (C 3 H 8 )  = 6 and  = 6 C balance:  = b H balance:  = 2c  c =  / 2 O balance: 2a = 2b + c  a = b + c / 2  a =  +  /4 N balance: 2 ( 3.76)a = 2d  d = 3.76a/2  d = 3.76(  +  / 4 ) C 6 H 6 + (7.5)(O 2 +3.76N 2 ) 6CO 2 +3H 2 O+3.76(7.5)N 2

4. Combustion Stoichiometry Note above equation only applies to stoichiometric mixture For benzene (C 6 H 6 ), (A/F) s = 13.2 The stoichiometric mass based air/fuel ratio for C  H  fuel is: The products of benzene: 6CO 2 +3H 2 O+3.76(7.5)N 2 =6 + 3 + 3.76x7.5 = 37.2 mol N 2 (%)=75.81% H 2 O(%)=8.1% CO 2 (%)=16.13%

12. Plotting >> dewpoint1=[58.53 54.666 47.087]; >> dewpoint2=[74.5 70.77 61.765]; >> dewpoint3=[84.431 80.5 71]; >> plot(afr,dewpoint1) >> hold on >> plot(afr,dewpoint2) >> hold on >> plot(afr,dewpoint3) >> grid