Question

Methane gas (CH4) is burned in a combustor with a given percentage of excess air. The pressure and temperature of both the air and fuel are 101 kPa and 298 K respectively. Assume that the mole fractions are 79% nitrogen and 21 % oxygen for air (use M=28.97 kg/kmol and R=0.287 kJ/kg-K) and that water is a vapor in the exhaust. Given the values below, determine the following:

--Given Values--

m_fuel (kg) = 100

Excess Air = 25%

a) Determine the air fuel ratio (kmol_air/kmol_fuel) Answer=11.905 +/- 7.9E-02

b) Determine the amount (kmol) of fuel burned. Answer=6.2344 +/- 4.2E-02

c) Determine the amount (kmol) of air used. Answer=74.219 +/- 4.9E-01

d) Determine the amount (kmol) of CO2 produce Answer=6.2344 +/- 4.2E-02

e) Determine the amount (kmol) of H2O produced. Answer=12.4688 +/- 8.3E-02

f) Determine the amount (kmol) of N2 produced. Answer=58.6332 +/- 3.9E-01

g) Determine the amount (kmol) of O2 produced Answer=3.1172 +/- 2.1E-02

h) Determine the Enthalpy (kJ) of the reactants. Answer=-466646 +/- 3.1E+03

i) Determine the adiabatic flame temperature (K). Answer=2015.16 +/- 1.3E+01

j) Determine the Enthalpy (kJ) of CO2 in the products Answer=-1877561 +/- 1.3E+04

k) Determine the Enthalpy (kJ) of H2O in the products. Answer=-2099174 +/- 1.4E+04

l) Determine the Enthalpy (kJ) of N2 in the products. Answer=3323766 +/- 2.2E+04

m) Determine the Enthalpy (kJ) of O2 in the products. Answer=186323 +/- 1.2E+03

Answer 1