Experimental Investigations on Multiphase Phenomena in Porous Media

Modeling of waterflow and solute transport in porous media is typically based on the water dynamics only, while the gaseous phase is neglected. Since the two fluids share the same pore space a particular investigation of the gaseous phase is mandatory to understand its influence on the basic processes (continuity, hysteresis, entrapment,. . . ) especially near water saturation. For the multiphase measurements an existing multistep outflow setup for determination of hydraulic properties with laboratory sized columns, was improved by an additional air-flow measurement device where gas phase continuity and conductivity could be measured simultaneously. Measured hydraulic data was analyzed by inverse modeling on which the pneumatic data analysis was based. Several gas conductivity models were tested. The possibilities of a combined measurement of hydraulic and pneumatic properties were demonstrated with artificial porous media made of sintered glass. The comparison of measurement and simulations of air conductivity showed the necessity of a rescaling of the effective air saturation for predictions. The influence of the sample structure on the hydraulic and pneumatic properties was illustrated with several homogenous and heterogeneous samples of repacked sands. The differences between purely hydraulic and combined measurement could be shown with experiments carried out with two pathologic structures. For this samples the basic structure elements could be detected by the combination of hydraulic and pneumatic measurements.

Level thesis:degree_level

thesis.doctoral

Grantor dc:publisher

Universität Heidelberg

Year

2004

Author dc:creator

• Graf, Hans

Contributors dc:contributor

• Roth, Kurt

Repository record source_url

http://www.ub.uni-heidelberg.de/archiv/4590

OAI identifier oai:identifier

oai:archiv.ub.uni-heidelberg.de:4590