TY - JOUR

T1 - Evaporation into half-space: Kinetic simulation of Knudsen layer for monatomic gas

AU - Morozov, Alexey A.

AU - Graur, Irina A.

AU - Гатапова, Елизавета Яковлевна

N1 - The study was supported by the Russian Science Foundation (Project No. 20-19-00722, https://rscf.ru/en/project/20-19-00722/ ) for E.G. and A.M.

PY - 2024/6/1

Y1 - 2024/6/1

N2 - Tools for modeling phase change processes in confined spaces are necessary to estimate heat and mass fluxes impacted by micro-level effects. We develop and validate numerical models for the simulation of evaporation processes using the direct simulation Monte Carlo method and the S-model kinetic equation. The numerical results are compared with previous results obtained by Sone and Sugimoto using the Boltzmann-Krook-Welander kinetic equation. The method of moments for the solution of the Boltzmann equation is also applied. The profiles of macroscopic parameters in the Knudsen layer are analyzed in detail. A very good agreement among the results given by all the applied models is found for a Mach number up to 1. As the considered approaches differ only in the collision laws, the evaporation parameters (temperature, pressure ratios, and the evaporation rate) seem relatively insensitive to the collision law models. The analytical solutions for the marcoscopic profiles (temperature, velocity, density, and pressure) are in good agreement with the numerical results. Possible criteria for Knudsen layer thickness estimation are suggested and tested. The provided results could be used as reference data to test evaporation models.

AB - Tools for modeling phase change processes in confined spaces are necessary to estimate heat and mass fluxes impacted by micro-level effects. We develop and validate numerical models for the simulation of evaporation processes using the direct simulation Monte Carlo method and the S-model kinetic equation. The numerical results are compared with previous results obtained by Sone and Sugimoto using the Boltzmann-Krook-Welander kinetic equation. The method of moments for the solution of the Boltzmann equation is also applied. The profiles of macroscopic parameters in the Knudsen layer are analyzed in detail. A very good agreement among the results given by all the applied models is found for a Mach number up to 1. As the considered approaches differ only in the collision laws, the evaporation parameters (temperature, pressure ratios, and the evaporation rate) seem relatively insensitive to the collision law models. The analytical solutions for the marcoscopic profiles (temperature, velocity, density, and pressure) are in good agreement with the numerical results. Possible criteria for Knudsen layer thickness estimation are suggested and tested. The provided results could be used as reference data to test evaporation models.

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85196101750&origin=inward&txGid=ce5746023b8d8fceb9482c897b049a24

UR - https://www.mendeley.com/catalogue/e7e160b2-e3e9-3626-8c29-348297a06a08/

U2 - 10.1063/5.0211993

DO - 10.1063/5.0211993

M3 - Article

VL - 36

JO - Physics of Fluids

JF - Physics of Fluids

SN - 1070-6631

IS - 6

M1 - 062013

ER -