Combustion Gas Properties: Part II—Prediction of Partial Pressures of CO₂ and H₂O in Combustion Gases of Aviation and Diesel Fuels

Empirical formulae are presented by means of which the partial pressures of CO₂ and H₂O in the combustion gases of aviation fuel-air and diesel fuel-air systems can be calculated as functions of pressure, temperature, equivalence ratio, and hydrogen-to-carbon atomic ratio of the fuel. The formulae have been developed by fitting the data from a detailed chemical equilibrium code to a functional expression. Comparisons of the results from the proposed formulae with the results obtained from a chemical equilibrium code have shown that the mean absolute error in predicted partial pressures is around 0.8 percent. These formulae provide a very fast and easy means of predicting partial pressures of CO₂ and H₂O as compared to equilibrium calculations, and they are also applicable to gasolines, residual fuels, and pure alkanes and aromatics as well as aviation and diesel fuels.