A DSMC investigation of gas flows in micro-channels with bends

White, Craig and Borg, Matthew K. and Scanlon, Thomas J. and Reese, Jason M. (2013) A DSMC investigation of gas flows in micro-channels with bends. Computers and Fluids, 71. pp. 261-271. ISSN 0045-7930 (https://doi.org/10.1016/j.compfluid.2012.10.023)

[thumbnail of White_C_Et_Al_A_DSMC_investigation_of_gas_flows_in_mcro_channels_with_bends_2013]
Preview
Text. Filename: White_C_Et_Al_A_DSMC_investigation_of_gas_flows_in_mcro_channels_with_bends_2013.pdf
Accepted Author Manuscript
License: Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 logo

Download (2MB)| Preview

Abstract

Pressure-driven, implicit boundary conditions are implemented in an open source direct simulation Monte Carlo (DSMC) solver, and benchmarked against simple micro-channel flow cases found in the literature. DSMC simulations are then carried out of gas flows for varying degrees of rarefaction along micro-channels with both one and two ninety-degree bends. The results are compared to those from the equivalent straight micro-channel geometry. Away from the immediate bend regions, the pressure and Mach number profiles do not differ greatly from those in straight channels, indicating that there are no significant losses introduced when a bend is added to a micro-channel geometry. It is found that the inclusion of a bend in a micro-channel can increase the amount of mass that a channel can carry, and that adding a second bend produces a greater mass flux enhancement. This increase happens within a small range of Knudsen number (0.02 Knin 0.08). Velocity slip and shear stress profiles at the channel walls are presented for the Knudsen showing the largest mass flux enhancement.

ORCID iDs

White, Craig, Borg, Matthew K., Scanlon, Thomas J. ORCID logoORCID: https://orcid.org/0000-0002-6819-9277 and Reese, Jason M. ORCID logoORCID: https://orcid.org/0000-0001-5188-1627;