What is the dew point temperature of combustion products?
Explanation
The dew point temperature is an important practical parameter because condensation of water, which is often acidic, in exhaust systems can cause corrosion.
Other questions
In the context of combustion calculations, what is the idealized molar ratio of nitrogen to oxygen in the air?
What is the definition of the equivalence ratio in combustion analysis?
Determine the air-fuel ratio on a molar basis for the complete combustion of octane (C8H18) with the theoretical amount of air.
What is the standard reference state used for establishing an enthalpy datum for reacting systems?
A mixture is described as lean when its equivalence ratio is what?
What is the enthalpy of formation?
What does a negative sign for the enthalpy of formation of a compound signify?
How is the specific enthalpy of a compound at a state (T, p) other than the standard state evaluated for reacting systems?
Methane (CH4) is burned with dry air, and a dry basis molar analysis of the products is CO2, 9.7 percent; CO, 0.5 percent; O2, 2.95 percent; and N2, 86.85 percent. What is the air-fuel ratio on a mass basis? Use M_air = 28.97 and M_fuel = 16.04.
What is the difference between the higher heating value (HHV) and the lower heating value (LHV) of a fuel?
Liquid octane (C8H18) enters an internal combustion engine at 25 C and 1 atm and burns completely with theoretical air. The products leave at 890 K. What is the heat transfer from the engine in kW if the fuel flow rate is 1.8 x 10^-3 kg/s and the power output is 37 kW? For C8H18(l), the enthalpy of formation is -249,910 kJ/kmol.
What is the adiabatic flame temperature?
How does providing excess air (more than the theoretical amount) for complete combustion typically affect the adiabatic flame temperature?
What is the primary function of a fuel cell?
According to the third law of thermodynamics, what is the entropy of a pure crystalline substance at the absolute zero of temperature (0 K)?
What is the enthalpy of combustion for gaseous methane at 25 C and 1 atm, with liquid water in the products, in kJ/kmol of fuel? The enthalpies of formation are -74,850 for CH4(g), -393,520 for CO2(g), and -285,830 for H2O(l).
Liquid octane at 25 C burns with 400 percent theoretical air. What is the adiabatic flame temperature? For liquid octane, the enthalpy of formation is -249,910 kJ/kmol.
A fuel cell is different from a conventional power plant because it is NOT limited by the efficiency of a what?
For the combustion of liquid octane with the theoretical amount of air, the rate of entropy production is 5404 kJ/kmol K. For an environment at 25 C (298 K), what is the rate of exergy destruction per kmol of fuel?
What is meant by a 'dry product analysis' of combustion gases?
The total exergy of a system relative to a reference environment is the sum of which two components?
For the complete combustion of methane (CH4) with 150 percent theoretical air, what is the balanced chemical reaction equation?
What does the van't Hoff equation relate?
In a closed, rigid container, 1 kmol of gaseous methane and 2 kmol of oxygen initially at 25 C burn completely. The products are cooled to 900 K. What is the amount of heat transfer in kJ?
Which component is the primary constituent of natural gas?
What is the absolute entropy of liquid octane (C8H18) at the standard reference state of 25 C and 1 atm, in kJ/kmol K?
What is the value of the Gibbs function of formation for stable elements like O2 and N2 at the standard reference state?
In a Proton Exchange Membrane Fuel Cell (PEMFC), what are the products of the overall cell reaction when using hydrogen and oxygen as fuel and oxidizer?
What is chemical exergy?
An exergetic efficiency for an internal combustion engine is to be evaluated. The power developed is 37 kW, and the rate of exergy entering with the fuel is 85.2 kW. What is the exergetic efficiency?
For the combustion of a hydrocarbon fuel, when is combustion considered complete?
What is the enthalpy of reaction, ΔH, for an exothermic reaction?
What is the primary reason that ionization of a gas such as cesium increases as pressure is lowered at a constant temperature?
What is the higher heating value (HHV) of gaseous methane (CH4) in kJ/kg?
What is the value of the Gibbs function of formation for carbon dioxide (CO2) at 298K and 1 atm, in kJ/kmol?
How is the entropy of a component 'i' in an ideal gas mixture at temperature T and partial pressure p_i evaluated?
When analyzing air-conditioning systems that involve combustion, such as a furnace, what is a key simplifying assumption often made about the nitrogen in the air?
Determine the air-fuel ratio on a mass basis for the complete combustion of octane, C8H18, with 150 percent theoretical air. The molecular weight of air is 28.97 and for octane is 114.22.
What is the standard chemical exergy of gaseous nitrogen (N2) according to Model II in Table A-26?
When modeling combustion, gasoline is often simplified as which hydrocarbon?
If an endothermic dissociation reaction occurs during combustion, what is the effect on the final product temperature compared to the case without dissociation?
In the balanced reaction C8H18 + 12.5O2 + 47N2 -> 8CO2 + 9H2O + 47N2, are the moles of reactants equal to the moles of products?
Calculate the chemical exergy of liquid octane (C8H18) at 25 C and 1 atm in kJ/kmol, using the provided standard chemical exergies from Model II: e_ch(CO2) = 19,870, e_ch(H2O(l)) = 900, e_ch(O2) = 3970. The Gibbs function of formation for C8H18(l) is 6610, for CO2 is -394,380, for H2O(l) is -237,180, and for O2 is 0.
The change in Gibbs function (ΔG) for a reaction is calculated as -257,253 kJ/kmol at 298 K. What is the value of ln K (natural log of the equilibrium constant) for this reaction? The universal gas constant is 8.314 kJ/kmol K.
What is the lower heating value (LHV) of liquid octane (C8H18) in kJ/kg?
A reaction has a large positive value for the change in Gibbs function (ΔG > 0). What does this imply about the equilibrium constant K?
In a PEMFC, hydrogen ions (protons) are conducted through which component?
If a combustion process is endothermic, what can be said about its enthalpy of combustion?
In an exergy balance for a steady-state reacting system, the exergy of the incoming combustion air is often taken as zero. Why is this?