A new method for predicting transport properties of polar firn with respect to gases on the pore space scale
ABSTRACT. In this study a powerful tool to investigate the permeabilities and effective diffusion coefficients of polar firn is presented using a combination of an experimental method for three dimensional pore structure reconstruction and two models to simulate advective and diffusive transports of...
Main Authors: | , , |
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Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
2002
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Subjects: | |
Online Access: | https://epic.awi.de/id/eprint/4649/ https://epic.awi.de/id/eprint/4649/1/Fre2001c.pdf https://hdl.handle.net/10013/epic.15220 https://hdl.handle.net/10013/epic.15220.d001 |
Summary: | ABSTRACT. In this study a powerful tool to investigate the permeabilities and effective diffusion coefficients of polar firn is presented using a combination of an experimental method for three dimensional pore structure reconstruction and two models to simulate advective and diffusive transports of gases through the pore space. The reconstruction follows a semi-automated digital analysis of serial surface sections. The simulations are based on a three-dimensional lattice Boltzmann formulation. They separately solve the Navier-Stokes equation and the diffusive transport equations. In a first application effective diffusion coefficients and permeabilities are calculated from firn samples of a core drilled during the North-Greenland-Traverse 1993-95. The estimated relationships of diffusivity and permeability to the open porosity are expressed by power law functions with exponents 2.1 and 3.4, respectively. |
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