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Chemical active porous media with internal mass exchange
Author(s) -
Sauerwein Malte,
Steeb Holger
Publication year - 2018
Publication title -
pamm
Language(s) - English
Resource type - Journals
ISSN - 1617-7061
DOI - 10.1002/pamm.201800420
Subject(s) - polymer , porous medium , porosity , polyelectrolyte , materials science , phase transition , chemical engineering , permeability (electromagnetism) , characterisation of pore space in soil , aqueous solution , mass transfer , chemistry , composite material , chromatography , thermodynamics , membrane , organic chemistry , biochemistry , physics , engineering
The aim of this contribution is to model a multiphasic material subjected to internal phase transition. The material is composed of a porous matrix, while the pore space is simultaneously filled with an aqueous pore fluid and a visco‐elastic gel. The latter one is made of a granulate of cross‐linked polyelectrolytes, also known as superabsorbent polymers (SAPs). Depending on the pore fluid chemistry, e. g. the concentration of mobile ions, the polymer phase absorbs water from the pore fluid and transforms to a hydrogel. Since the hydro‐mechanical properties of the overall mixture, e. g. the intrinsic permeability, depends on the phase transition process in the void space, a reliable constitutive modeling for the inter‐phase mass exchange has been carried out. In addition, comparison with experimental data shows that the derived continuum model is able to mimic phase transition processes for different NaCl concentrations in the pore liquid.