Quantitative prediction of residual wetting film generated in mobilizing a two-phase liquid in a capillary model

This research studies the motion of immiscible two-phase liquid flow in a capillary tube through a numerical approach employing the volume of fluid method,for simulating the core-annular flow and water flooding in oil reservoirs of porous media.More specifically,the simulations are a representation of water flooding at a pore scale.A capillary tube model is established with ANSYS Fluent and verified.The numerical results matches well with the existing data available in the literature.Penetration of a less viscous liquid in a liquid of higher viscosity and the development of a residual wetting film of the higher viscosity liquid are thoroughly investigated.The effects of Capillary number,Reynolds Number and Viscosity ratio on the residual wetting film are studied in detail,as the thickness is directly related to the residual oil left in the porous media after water flooding.It should be noticed that the liquids considered in this research can be any liquids of different viscosity not necessarily oil and water.The results of this study can be used as guidance in the field of water flooding.

Influence of specimen-reconstituting method on the undrained response of loose granular soil under static loading

This paper describes the results of an experimental study on the undrained shear behaviour of loose sand collected from the location close to the epicenter of the recent Chlef （Algeria） Earthquake （October 10,1980）.The study focuses on the effects of the mode of the soil deposition on the liquefaction resistance of the Chlef sand.For this purpose,the results of undrained monotonic triaxial compression tests performed on samples with initial density of 0.29 under initial confining pressures ranged from 50 kPa to 200 kPa are presented.The specimens were prepared by two depositional methods namely dry funnel pluviation and wet deposition.It was found that there was a marked difference in the undrained behaviour of sand in terms of maximal deviatoric stress,peak strength,residual strength and excess pore water pressure,even though the density and stress conditions were identical.The conclusion was that the soil fabric was responsible for this result.The results indicated also that at low confining pressures,the specimens reconstituted by the wet deposition method exhibited complete static liquefaction （zero effective confining pressure and zero stress difference）.