(a)
The equilibrium composition of product gases.
(a)
Answer to Problem 37P
Thus, the equilibrium composition of mixture of
Explanation of Solution
Write the expression for the volume of oxygen used per lbmol of carbon monoxide
Here, gas constant is R, temperature is T, and pressure is P.
Calculate the mass flow rate of carbon monoxide
Here, volume flow rate of carbon monoxide is
Calculate the molar air fuel ratio
Here, number of moles of oxygen is
Express the stoichiometric reaction for the dissociation process.
From the stoichiometric reaction, infer that the stoichiometric coefficient for carbon monoxide
Express the actual reaction for the dissociation process.
From the actual reaction, infer that the equilibrium composition contains x amount of carbon dioxide
Express the formula for total number of moles
Here, number of moles of carbon dioxide is
Write the expression for the equilibrium constant
Conclusion:
Substitute
Substitute
Substitute
Substitute xfor
Convert the temperature unit from Rankine to Kelvin.
Refer table A-28, “natural logarithm of equilibrium constants”, select the value of
Substitute
Solve the equation and find the value of x as 0.9966.
Substitute 0.9966 for x in Equation (V).
Thus, the equilibrium composition of mixture of
(b)
The rate of heat transfer from the combustion chamber
(b)
Answer to Problem 37P
The rate of heat transfer from the combustion chamber is
Explanation of Solution
Write the expression for the energy balance equation for the combustion process.
Here, heat released during combustion is
Write the expression for the mass flow rate of CO
Write the expression for the rate of heat transfer
Conclusion:
Refer Table A-26, “Enthalpy of formation, Gibbs function of formation, and absolute entropy at
778F, 1 atm”, select the enthalpy of
Refer Table A-21, “Ideal-gas properties of carbon monoxide”, obtain the following properties of
Enthalpy of
Enthalpy of
Enthalpy of
Use interpolation to get the Enthalpy of water vapor at 3600 K
Here, Enthalpy of
Substitute
Refer Table A-26, “Enthalpy of formation, Gibbs function of formation, and absolute entropy at
778F, 1 atm”, select the enthalpy of
Refer Table A-20, ‘Ideal gas properties of carbon dioxide’ find out the following enthalpies at different temperature.
Enthalpy of
Enthalpy of
Enthalpy of
Similarly, use interpolation and obtain the enthalpy of
Refer Table A-26, “Enthalpy of formation, Gibbs function of formation, and absolute entropy at
778F, 1 atm”, select the enthalpy of
Refer Table A-19, ‘Ideal gas properties of oxygen’, choose the enthalpy at the following temperatures.
Enthalpy of
Enthalpy of
Enthalpy of
Similarly, use interpolation and obtain the enthalpy of
Substitute
Substitute
Substitute
Thus, the rate of heat transfer is
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Chapter 16 Solutions
Thermodynamics: An Engineering Approach
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