THEORETICAL INVESTIGATION OF CLUSTER-FORMATION DYNAMICS IN SUPERSONIC JETS

J. D. FUHR; P. FAINSTEIN; D. FREGENAL; E. KAÚL; P. KNOBLAUCH; A. LAMAGNA; P. MACEIRA; M. ZARCO; E. ZEMMA; J. FIOL

Stresa

Workshop; 14th International Workshop on Separation Phenomena in Liquids and Gases; 2017

Most of Molecular Laser-induced Isotope Separation (MLIS) schemes for uranium enrichment, rely on supercooling of the species of interest by adiabatic expansion of a gas jet of the molecules of interest in a carrier gas. This procedure allows to cool the molecules below their condensation point while remaining in a gaseous state, and thus suited for its irradiation by infrared radiation. The formation of small agregates, both homogeneous ((UF6)n) of different sizes as well as inhomogeneous clusters of the molecules with the carrier gas, occur as a consequence of the collisions of the different particles in the gas, in a rather complex dynamics. It is of great interest to be able to manipulate the formation of clusters through macroscopic parameters such as pressure, temperature, concentration of the molecule, etc. In this communication we present theoretical investigations on the formation of SF 6 −Ar dimers simulating the two-body collisions in a Classical-Trajectory-Monte-Carlo approach. We used intra- and inter-molecule potentials obtained from ab-initio quantum-mechanical calculations. This approach allow us to calculate several magnitudes of interest, linked to macroscopic quantities. In particular we obtain values for cross-sections, probability of formation, lifetime, and energy transfer of the formed clusters.