INVESTIGATION OF MIXING IN BINARY GAS MIXTURES UNDER MECHANICAL EQUILIBRIUM INSTABILITY

V. Mukamedenkyzy; B.E. Akberdiyev

doi:10.31489/2026N2/108-117

Authors

DOI:

https://doi.org/10.31489/2026N2/108-117

Keywords:

diffusion, convection, mechanical equilibrium, binary gas mixture

Abstract

Mixing processes in binary and multicomponent gas systems are characterized by a significant variety of observed regimes. The main objective of the study is to determine the boundary between diffusion and convective regimes, as well as to identify the parameters that control the convective regime. The change in modes from "isothermal diffusion" to "gravitational concentration convection" was studied using the ANSYS Fluent software package, which allows investigating the evolution of convective flows at the initial stage of mixing and determining the limits of mechanical equilibrium stability of the system. The observed correspondence between computational and experimental results verifies the proposed method for determining the boundary between diffusion and convective transport in gas mixtures. The novelty lies in reconstructing the spatiotemporal evolution of the isoconcentration fields for binary mixtures at different pressures and relating the convective flow structures to the observed mode transitions. The approach provides a verified method for locating the diffusion–convection boundary and for refining diffusion and thermal-diffusion coefficient measurements.

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INVESTIGATION OF MIXING IN BINARY GAS MIXTURES UNDER MECHANICAL EQUILIBRIUM INSTABILITY