Iranian Institute of Research and Development in Chemical Industries (IRDCI)-ACECRNashrieh Shimi va Mohandesi Shimi Iran1022-776841220220823Discussion on the Separation Factor of the Gaseous Diffusion System for Binary Isotope Separation of UF6 by Direct Simulation Monte Carlo MethodDiscussion on the Separation Factor of the Gaseous Diffusion System for Binary Isotope Separation of UF6 by Direct Simulation Monte Carlo Method34135146352FAMajid Abedi MasirDepartment of Fuel Cycle, Faculty of Nuclear Engineering, Shahid Beheshti University, Tehran, I.R. IRANMahdi AqaieDepartment of Fuel Cycle, Faculty of Nuclear Engineering, Shahid Beheshti University, Tehran, I.R. IRANJournal Article20191225<em>Aim of this research is to investigate the effect of the flow regime on separation in the gaseous diffusion system, the effect of the Knudsen number on the separation factor, and the diffusion velocity of the particles. In the current research, firstly, a brief description of the theory that governs the system will be given. Then, with the simulation of an element, the effect of the type of flow regime and Knudsen number on the variation of enrichment, the separation factors and the diffusion velocity of the light and heavy components inside the pores are investigated. Results are compared by theoretical equations. It is also should mentioning that two light and heavy isotopes of UF6 gas have been used for separation by gaseous diffusion method. The results will show; separation does not occur in the continuous flow regime, and separation will be occurring only in the molecular and transient flow regime. Also, with the increment of the Knudsen number, the amount of changes in the enrichment in different parts of the system will increase compared to the incoming gas. In other words, with the increment of Knudsen number, more separation is formed and the separation factor of the system increases. For instance, for a Knudsen number of 0.1, the separation factor is equal to 1.00101, and for a Knudsen number of 0.8, this value will increase to 1.00333. Finally, the diffusion velocity of the particles inside the pores, which is criteria of the effective separation of the particles, has been investigated. The results show that the diffusion velocity of particles for the light component is higher than heavy component, and this is due to the higher intensity of the particles of the light component passing through the pores.</em><em>Aim of this research is to investigate the effect of the flow regime on separation in the gaseous diffusion system, the effect of the Knudsen number on the separation factor, and the diffusion velocity of the particles. In the current research, firstly, a brief description of the theory that governs the system will be given. Then, with the simulation of an element, the effect of the type of flow regime and Knudsen number on the variation of enrichment, the separation factors and the diffusion velocity of the light and heavy components inside the pores are investigated. Results are compared by theoretical equations. It is also should mentioning that two light and heavy isotopes of UF6 gas have been used for separation by gaseous diffusion method. The results will show; separation does not occur in the continuous flow regime, and separation will be occurring only in the molecular and transient flow regime. Also, with the increment of the Knudsen number, the amount of changes in the enrichment in different parts of the system will increase compared to the incoming gas. In other words, with the increment of Knudsen number, more separation is formed and the separation factor of the system increases. For instance, for a Knudsen number of 0.1, the separation factor is equal to 1.00101, and for a Knudsen number of 0.8, this value will increase to 1.00333. Finally, the diffusion velocity of the particles inside the pores, which is criteria of the effective separation of the particles, has been investigated. The results show that the diffusion velocity of particles for the light component is higher than heavy component, and this is due to the higher intensity of the particles of the light component passing through the pores.</em>https://www.nsmsi.ir/article_46352_3e24e98c16576d8b9cc8faec9f050ef5.pdf