Velocity fluctuations in slow flow through porous media

In this thesis, I study the spatial statistical properties of slow flow through porous media on the pore scale by a combination of numerical simulation and theoretical arguments. I demonstrate that the flow patterns undergo a transition from swirls to strongly focused and channel-like patterns for decreasing porosities. Not only is the flow in low-porosity media strongly focused, but the flow also possesses long-tailed, non-Gaussian velocity probability density distributions. A main result of our simulations is that the statistics of the flow through a single channel captures the entire flow, insofar as the patterns and probability distributions are concerned. I have constructed a simplified, phenomenological model for the fast part of the flow in random porous media. This model yields the desired exponential velocity distributions. For high porosities, I find that the statistical properties of the velocity fluctuations behave in a similar way as those observed in dilute suspensions flows: the swirls have a power-law dependency on the solid volume fraction, the correlation length is finite and has also a power-law dependency. I demonstrate that this scaling behavior is consistent with the predictions of theories. Finally, I study creeping flow through a single rough walled channel by numerical simulation and present a theory that predicts scale dependency of the permeability for tight fractures.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Earth, Atmospheric, and Planetary Sciences

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

1998

Author dc:creator

• Van Genabeek, Olav (Olav Arnold)

Advisor dc:contributor.advisor

• Daniel H. Rothman.

• Earth, Atmospheric, and Planetary Sciences

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/58059

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/58059