The Knudsen Paradox in Micro-Channel Poiseuille Flows with a Symmetric Particle
Journal article, 2021

The Knudsen paradox—the non-monotonous variation of mass-flow rate with the Knudsen number—is a unique and well-established signature of micro-channel rarefied flows. A particle which is not of insignificant size in relation to the duct geometry can significantly alter the flow behavior when introduced in such a system. In this work, we investigate the effects of a stationary particle on a micro-channel Poiseuille flow, from continuum to free-molecular conditions, using the direct simulation Monte-Carlo (DSMC) method. We establish a hydrodynamic basis for such an investigation by evaluating the flow around the particle and study the blockage effect on the Knudsen paradox. Our results show that with the presence of a particle this paradoxical behavior is altered. The effect is more significant as the particle becomes large and results from a shift towards relatively more ballistic molecular motion at shorter geometrical distances. The need to account for combinations of local and non-local transport effects in modeling reactive gas–solid flows in confined geometries at the nano-scale and in nanofabrication of model pore systems is discussed in relation to these results.

Knudsen minimum

rarefied flows

micro-channel

Knudsen paradox

Poiseuille flow

DSMC

Author

Ananda Subramani Kannan

Chalmers, Mechanics and Maritime Sciences, Fluid Dynamics

Tejas Sharma Bangalore Narahari

Chalmers, Mechanics and Maritime Sciences, Fluid Dynamics

Yashas Bharadhwaj

Chalmers, Mechanics and Maritime Sciences, Fluid Dynamics

Andreas Mark

Fraunhofer-Chalmers Centre

Gaetano Sardina

Chalmers, Mechanics and Maritime Sciences, Fluid Dynamics

Dario Maggiolo

Chalmers, Mechanics and Maritime Sciences, Fluid Dynamics

Srdjan Sasic

Chalmers, Mechanics and Maritime Sciences, Fluid Dynamics

Henrik Ström

Chalmers, Mechanics and Maritime Sciences, Fluid Dynamics

Applied Sciences

1454-5101 (ISSN)

Vol. 11 1 1-13 351

A continuum model for Brownian motion in rarefied gas-solid flows

Swedish Research Council (VR), 2016-01-01 -- 2019-12-31.

Subject Categories

Fluid Mechanics and Acoustics

DOI

10.3390/app11010351

More information

Latest update

1/21/2021