Analytic Solution for the Equilibrium Composition of a Carbon- Nitrogen-Oxygen Gas Mixture.

摘要

An approximate analytic solution has been developed for the equilibrium composition of a gas mixture whose elemental composition consists of carbon-nitrogen-oxygen and an inert species. Neither condensed nor ionized species are considered. Trace species are ignored. The species composition is determined for given elemental mass fractions, temperature, and density or pressure. The error in mixture properties is a maximum of four percent and is generally less than one percent. The computation speed ranges from two-to-three orders of magnitude faster than exact calculation procedures, depending upon the initial guess supplied to the exact calculation. The analytic solution is particularly suited for use in boundary layer calulations over an ablating carbon surface. It should also find use in planetary entry applications and other fluid dynamic problems where the gas of interest contains carbon, nitrogen, and oxygen species.