Steady-state filtration in a piecewise homogeneous stratum, separated by a thin layer

Motivated by the geological sequestration of carbon dioxide (CO2), we study the propagation of gravity currents in a porous medium bounded by a thin layer of much lower permeability. We formulate a model for drainage assuming that the fluid remains simply connected throughout. Using this model we examine the propagation of both two-dimensional and axisymmetric currents numerically. We find that for the fixed-flux situation solutions approach a steady state which is described analytically. The approach to this final solution depends on both the permeability contrast and thickness of the thin layer, and in many cases the current first overshoots before relaxing back to its ultimate steady state. Finally, we examine propagation along multiple thin, lower permeability layers as a reduced-order model of the plume of CO2 currently being injected at Sleipner in the North Sea.

Download Full-text

Steady-state mass transfer in radial flow-through thin layer cells—I. Reversible metal systems

Electrochimica Acta ◽

10.1016/0013-4686(81)85112-2 ◽

1981 ◽

Vol 26 (9) ◽

pp. 1289-1297 ◽

Cited By ~ 2

Author(s):

D. Bürgi ◽

P. Noorlander ◽

H. Siegenthaler

Keyword(s):

Mass Transfer ◽

Steady State ◽

Thin Layer ◽

Radial Flow ◽

Flow Through

Download Full-text

Effect of adding simultaneous hydrophilic and microporous layers on water transport in the gas diffusion layer of polymer electrolyte membrane fuel cell

Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy ◽

10.1177/09576509211022997 ◽

2021 ◽

pp. 095765092110229

Author(s):

Yaghoub Ira ◽

Younes Bakhshan ◽

Jamshid Khorshidimalahmadi

Keyword(s):

Steady State ◽

Fuel Cell ◽

Thin Layer ◽

Polymer Electrolyte ◽

Liquid Water ◽

Water Saturation ◽

Polymer Electrolyte Membrane ◽

Gas Diffusion ◽

Electrolyte Membrane ◽

Time Required

In this study, the effect of location, wettability, and thickness of the hydrophilic layer and also the effect of microporous layer (MPL) thickness on the dynamic water transport in the gas diffusion layer (GDL) of polymer electrolyte membrane fuel cell (PEMFC) is investigated using the Lattice Boltzmann method. The effect of the presence of hydrophilic layer and MPL on the number of dominant flow paths, liquid water breakthrough sites, liquid water loops, liquid water pools, and time required to reach steady-state for 12 cases have been investigated. Results showed that if the hydrophilic layer is near the MPL/GDL interface, flooding will occur. Also, comparing with purely hydrophobic GDL, reduction of hydrophilic layer thickness in the GDL/GC interface reduces the water saturation level by 11.8% and the time required to reach steady-state by 8.88%. Moreover, this study indicated that adding a thin layer of MPL at the catalyst layer (CL)/GDL interface with present a hydrophilic thin layer at the GDL/gas channel (GC) interface reduces the liquid water saturation level by 50.1% and the steady-state time by 38.9%. Furthermore, the details of the dynamic behavior of water in the GDL under different hydrophilic conditions have been reported and discussed.

Download Full-text

Thin-layer steady-state voltammetry under control by diffusion and migration

Canadian Journal of Chemistry ◽

10.1139/v88-215 ◽

1988 ◽

Vol 66 (5) ◽

pp. 1333-1341 ◽

Cited By ~ 10

Author(s):

Christa L. Colyer ◽

Paul J. J. Connelly ◽

Heather L. Gordon ◽

Keith B. Oldham

Keyword(s):

Steady State ◽

Thin Layer ◽

Stringent Test ◽

And Migration ◽

Electrochemical Transport

Measurements of steady-state currents in thin-layer cells provide an opportunity to apply a stringent test of theories of electrochemical transport by simultaneous diffusion and migration. We have applied such a test and find the theory to be vindicated.

Download Full-text