Gas Mixture

1.An ideal gas mixture has the following stoichiometric analysis

Component % by mass

N₂ 40

CO₂ 10

CO 13

O₂ 17

H₂ 08

CH₄ 12

(A) Find the analysis on a volume basis.

(B) What is the volume of 1 kg of this gas when the P = 1.5 MPa and T = 30^oC?

(C) Find the specific heats at 300 K. Using Table A.2

(D) This mixture undergoes an expansion isentropic process from 2.0 bar, 130^oC to 1 MPa. Find T₂.

(F) Find Ds_m per kg of mixture when the mixture is compressed isothermally from 0.1 MPa to 0.2 MPa.

(G) All the gases are supplied in separate lines at 0.2 MPa and 300 K to a mixing chamber and are mixed adiabatically. The resulting mixture has the composition as given in Part (A). Determine the entropy change due to the mixing process per unit mass of mixture.

2.An ideal gas mixture has the following volumetric analysis: N₂ = 55%, CO₂ = 25%, O₂ = 20% is compressed adiabatically in a Piston-Cylinder assembly from 1 bar 20 ⁰C to 5 bar.

(A) Find the analysis on a mass basis.

(B) Find the specific heats at 350 K. Using Table A.2

(C) Determine the work required for compression process?

(D) Find Ds_m per kg of mixture

(E) If the mixture undergoes an isothermal process from 2.0 bar, 130^oC to 1 bar. What wouldDs_m of mixture be?

(F) If heat added to the mixture after compression till its temperature becomes 1000 ⁰C, calculate the amount of heat added.

Combustion

3. Calculate the volumetric A/F ratio and percentage of CO₂ by volume in the DRY products when methane is stoichiometrically burned with air.

4. A boiler burns fuel oil with the following analysis by mass: 80% C; 185 H₂; 2% S.

30% excess air is supplied to the process. Calculate the stoichiometric ratio by mass and the % Carbon Dioxide present in the DRY product.(15.62/1; 14.9% CO₂)

5. Calculate the % of each DRY product when coal is burned stoichiometrically in air. The mass analysis of the coal is: 80% C; 10% H₂; 5% S; and 5% ash.

(76.7%N, 22.5%CO₂; 0.8% SO₂)

6. A fuel is a mixture of 60% Methane, 30% carbon monoxide, and 10% Oxygen by volume. Calculate the stoichiometric Oxygen needed. (1.25 m³)

7. A gaseous fuel contains the following analysis by volume: 5% CO₂; 40% H₂; 40% CH₄; 15% N₂. Determine the stoichiometric air and the % content of each DRY product. (4.76m³, 89.7% N₂, 10.3% CO₂)

8. Find the air fuel ratio for stoichiometric combustion of Butane by volume. Calculate the percentage of carbon dioxide present in the DRY flue gas if 30% excess air is used. (30.95/1; 10.6%)

9. Find the air fuel ratio for stoichiometric combustion of propane by volume. Calculate the percentage of Oxygen present in the DRY flue gas if 20% excess air is used.

(23.81/1; 3.8%)

10. A gaseous fuel contains the following by Mass: 5% CO₂; 40% H₂; 40% CH₄; 15% N₂. Determine the gravitational stoichiometric air and the % content of each WET product by mass.