20.500.12556/DiRROS-21005 Numerical analysis of knudsen number of helium flow through gas-focused liquid sheet micro-nozzle This work aims to verify whether the continuum mechanics assumption holds for the numerical simulation of a typical sample delivery system in serial femtosecond crystallography (SFX). Knudsen numbers were calculated based on the numerical simulation results of helium flow through the gas-focused liquid sheet nozzle into the vacuum chamber, representing the upper limit of Knudsen number for such systems. The analysed flow is considered steady, compressible, and laminar. The numerical results are mesh-independent, with a Grid Convergence Index significantly lower than 1% for global and local analysis. This study is based on an improved definition of the numerical Knudsen number: a combination of the cell Knudsen number and the physical Knudsen number. In the analysis, no-slip boundary and low-pressure boundary slip conditions are compared. No significant differences are observed. This study justifies using computational fluid dynamics (CFD) analysis for SFX sample delivery systems based on the assumption of continuum mechanics. Knudsen number compressible hypersonic flow vacuum liquid sheet nozzle sample delivery system CFD true false true MDPI Švica Angleški jezik Ni določen © 2024 by the authors Neznano 2024-12-17 08:15:05 2024-12-17 08:15:06 2024-12-18 03:55:06 0000-00-00 00:00:00 2024 0 0 Nasl. z nasl. zaslona; Opis vira z dne 22. 11. 2024; str. 1-15 iss. 12, [art. no.] 273 Vol. 9 2024 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 2024-12-01 532 2311-5521 10.3390/fluids9120273 216132867 RAZ_Kovacic_Kristof_2024.pdf RAZ_Kovacic_Kristof_2024.pdf 1 2D504A5A9ACC62751094413B06B79CFE b9b34643e88d5c98a16aea02d2466eae98b2a761447de981edd51321c0c0658d ef87e414-bc4a-11ef-ba3f-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=29735 https://www.mdpi.com/2311-5521/9/12/273 1 a53413b7-bc46-11ef-ba3f-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=29732 Inštitut za kovinske materiale in tehnologije 0 0 0