Influence of the Flow Direction on the Mass Transport of Vapors through Membranes Consisting of Several Layers

0445186 - ÚCHP 2016 RIV US eng J - Journal Article
Loimer, T. - Uchytil, Petr
Influence of the Flow Direction on the Mass Transport of Vapors through Membranes Consisting of Several Layers.
Experimental Thermal and Fluid Science. Roč. 67, OCT 2015 (2015), s. 2-5. ISSN 0894-1777. E-ISSN 1879-2286.
[International conference on Heat Transfer and Fluid Flow in Microscale (HTFFM-V) /5./. Marseilles, 22.04.2014-25.04.2014]
R&D Projects: GA MŠMT 7AMB12AT010; GA MŠMT(CZ) 7AMB14AT011
Institutional support: RVO:67985858
Keywords : porous media * phase change * vapor flow
Subject RIV: CI - Industrial Chemistry, Chemical Engineering
Impact factor: 2.128, year: 2015

The flow of vapors with possible condensation is described, taking into account the energy balance, the Joule-Thomson effect and possible capillary condensation. For vapors close to saturation, the mass flux may be several times larger in one flow direction than in the opposite flow direction through an asymmetric membrane. As an example, the flow of isobutane through a porous ceramic membrane consisting of three different layers is theoretically investigated. The individual layers have different thicknesses with pore sizes of 10 nm for the separation layer, 100 nm for the middle layer and 6 μ m for the support layer. For a small ratio of the upstream pressure to the saturation pressure, the fluid does not condense within the porous membrane, and the mass flux is a few percent larger for the flow direction from the support to the separation layer than for the other flow direction. For larger upstream pressures, the fluid may condense and the mass flow can become about 7 times larger for one flow direction than for the opposite flow direction.
Permanent Link: http://hdl.handle.net/11104/0248079