Abstract: Considering gas-dynamic processes associated with the combustion of various fuels in rocket engines, the problem of determining the equilibrium composition of combustion products and their properties, as well as the heat effect of the reaction arises. The equilibrium composition of a mixture can be calculated by methods based on the equilibrium constant as well as by minimising the thermodynamic potentials: the Gibbs energy (isobaric potential) or the Helmholtz energy (isochoric potential). The calculation of the equilibrium composition using the equilibrium constants is a very inconvenient method, as it requires detailed information about the chemical reactions, which in most cases are poorly known. The calculation of equilibrium by minimisation of thermodynamic potentials requires only data on the initial composition and on the thermodynamic properties of the substances that will be part of the reaction products. The calculation method of the equilibrium composition of combustion products by Gibbs energy minimization and its programming implementation are considered in this article.

Keywords: equilibrium composition, Gibbs energy, multi-component optimization.

For citation: Smirnov P. G. Calculating equilibrium composition of fuel compositions combustion products by minimising the thermodynamic potential. Aerospace Engineering and Technology. 2023. Vol. 1. No. 1, pp. 160–172.