Visualization and Simulation of Imbibition in Matrix-Fracture
dc.contributor.author | Haghighi, M. | |
dc.contributor.author | Shariatpanahi, F. | |
dc.contributor.author | Yortsos, Y. | |
dc.contributor.conference | Canadian International Petroleum Conference (6th : 2005 : Calgary, Canada) | |
dc.date.issued | 2005 | |
dc.description.abstract | <jats:sec> <jats:title>Abstract</jats:title> <jats:p>To predict the ultimate oil recovery more realistically from naturally fractured reservoirs during water displacement, the knowledge of flow behavior in the matrix-fracture systems at pore level is very important. The main purpose was the visual assessment of some unclear theories that have been put forward to explain the production behavior of fractured oil reservoirs with water drive or during water injection.</jats:p> <jats:p>Two series of experiment were implemented on transparent glass-etched micromodel; one without the gravity effects at various capillary number values (Nc) and mobility ratios (M), and another under the gravity effects at different Nc and constant M.</jats:p> <jats:p>In the experiments without effects of gravity; it was observed that at low Nc the wetting fluid preferentially invaded the matrix. Two critical capillary numbers were identified, one for the start of penetration in the fracture when the viscosity ratio was much less than one, and another for which the rate of propagation of the front in the fracture is the same with that in the matrix, when the viscosity ratio was greater than one. These critical capillary numbers were well matched with the results of a pore network simulation. Free imbibition in fractured system was also investigated and compared favorably with pore network simulation. This process first involves the rapid invasion of the matrix, followed by the subsequent penetration of the fracture. A simplified theory was also developed for the experiments.</jats:p> <jats:p>All experiments under gravity effects were implemented on three types of micromodels with different fracture orientations and gravity effects. The amount of oil recovery from the matrixfracture systems at various capillary numbers was determined and the results were compared with the model with no fracture. The results suggest that the amount of oil recovery by water displacement under the water-wet condition of our model is not very sensitive to the fracture orientation.</jats:p> <jats:sec> <jats:title>Introduction</jats:title> <jats:p>The understanding of water injection in fractured systems iscurrently based mostly on phenomenology and typically consists of applying a double porosity formalism to reservoir simulators. Most of these simulators use capillary imbibition as a mechanism for the exchange of fluids between the matrix blocks and the fracture network20. Such a purely numerical approach offers little to further our insight into the process. A reasonable alternative is to conduct experiments in model geometries that mimic fractured systems. Glass micro models can be constructed to mimic there.</jats:p> <jats:p>Immiscible displacement in disordered porous media proceeds by different mechanisms, depending on the nature andhistory of the displacement (drainage or imbibition, primary or secondary process). These mechanisms have been clearly elucidated in recent years, notably by Lenormand who conducted careful experimental studies in micromodel geometries15. The local displacement mechanics are not expected to change when a fracture-matrix system is considered. Thus, primary displacements will proceed by a frontal advance of the menisci, the conditions for which vary depending on whether the process is drainage or imbibition, the latter including the possibility of flow along the surface roughness. Secondary imbibition will involve in addition filmflow, film thickening and snap-off, resulting at low rates in displacements different than frontal.</jats:p> </jats:sec> </jats:sec> | |
dc.description.statementofresponsibility | F. Shariatpanahi, M. Haghighi, Y. C. Yortsos | |
dc.identifier.citation | Sixth Canadian International Petroleum Conference, 2005: pp. 1-16 | |
dc.identifier.doi | 10.2118/2005-108 | |
dc.identifier.isbn | 9781613991121 | |
dc.identifier.orcid | Haghighi, M. [0000-0001-9364-2894] | |
dc.identifier.uri | http://hdl.handle.net/2440/70689 | |
dc.language.iso | en | |
dc.publisher | PETSOC | |
dc.rights | Copyright 2005. Petroleum Society of Canada | |
dc.source.uri | http://www.onepetro.org/mslib/servlet/onepetropreview?id=PETSOC-2005-108 | |
dc.title | Visualization and Simulation of Imbibition in Matrix-Fracture | |
dc.type | Conference paper | |
pubs.publication-status | Published |