Thermodynamic modelling of rotating detonation engines cycles

This work aims to perform a thermodynamic comparison of the thermal efficiency of gas turbines operating with a combustion chamber and a detonation chamber, using methane, ethanol and mixtures of ethanol and hydrogen and methane and hydrogen as fuels. Based on the study of combustion reactions in the context of equilibrium thermodynamics, a computational model was developed in order to study the combustion and detonations processes. The composition of the gases is determined by the minimization of the Gibbs free energy and the temperature, pressure and speed of detonation are determined by the Chapman-Jouguet theory. The results obtained showed that the detonation thermodynamic cycle had a higher compressor work, turbine work, turbine net work output and thermal efficiency than the constant-pressure combustion cycle for all fuels considered. The maximum thermal efficiency obtained with the detonation cycle was 48.88%, which is a 42.91% improvement over the maximum thermal efficiency obtained with the constant-pressure combustion cycle.