عنوان مقاله [English]
The Boltzmann equation is a very important equation in the physics and fluid dynamics which describes binary collisions between molecules. The direct use of Boltzmann equation for rarefied gases is difficult and hard due to nonlinearity and complexity of collision integral expressions. Direct simulation Monte-Carlo is one of the methods to solve the Boltzmann equation. Moisture may leaks to the fluid pipelines in the various places of cascades so many times through the enrichment operations since pressure of the most enrichment process units is less than the atmospheric pressure. It causes the solid uranium precipitation on the inner surfaces of rotor and HF production upon the reaction with UF6. It has been investigated the impact of concentration and total pressure inside a hypothetical centrifuge for binary component conditions (ZUF6=0.97, ZHF=0.03), (ZUF6=0.93, ZHF=0.07), (ZUF6=0.9, ZHF=0.1), (ZUF6=0.85, ZHF=0.15) and three component conditions (ZUF6=0.9, ZHF=0.05, ZAir=0.05) and (ZUF6=0.8, ZHF=0.1, ZAir=0.1) in this research. The results have been compared with the Boltzmann distribution function. Moreover, increase in the amount of light gas along with UF6 results in the decrease of ρv_z.