Laminar-turbulent cycles in inclined lock-exchange flows

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Imbibition Capillary Pressure and Relative Permeability of Mixed-Wet Microporous Rock : New Insights from History Matching

MC was supported by the University of Aberdeen College of Physical Sciences studentship. The authors gratefully acknowledge CYDAREX for providing an evaluation license for their software CYDARTM , Koon-Yang Lee for the n-decane/brine static contact angle measurements on calcite (Supplementary Material S3), and Steffen Berg for his insightful comments and suggestions as a reviewer for conference paper Christensen and Tanino 2018 on which this paper builds. Finally, the authors thank the three anonymous reviewers for their detailed comments. All data used in this study are available from the corresponding author on reasonable request. In addition, the centrifuge data generated during this study are included as a Excel spreadsheet in the supplementary materials for this published article. One set of mercury injection capillary pressure measurements by Tanino and Blunt (2012) analysed in Text S2 are available in the Mendeley data repository, https://data.mendeley.com/datasets/9f4898jfr9/1.Peer reviewedPostprin

Recreating mineralogical petrographic heterogeneity within microfluidic chips : assembly, examples, and applications

This material includes work supported by Royal Society Research Grant RG140009. BA was supported by a Society of Petrophysics and Well Log Analysts (SPWLA) grant and an Aberdeen Formation Evaluation Society (AFES) bursary. MC was supported by a University of Aberdeen College of Physical Sciences PhD studentship. The authors thank Munasuonyu Walter for SEM images of crushed marble†, MSc students Oluwatoyole A. Adepoju and Vasiliki Koutsogianni for their contribution to the experiments, and undergraduate student Duncan Mackenzie for helpful discussions. Open Access via RSC Gold 4 GoldPeer reviewedPublisher PD

Aquatic gravity currents through emergent vegetation

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (leaves 109-112).Differential heating and cooling can generate density-driven, lateral exchange flows in aquatic systems. Despite the ubiquity of wetlands and other types of aquatic canopies, few studies have examined the hydrodynamic effects of aquatic vegetation on these currents. This study investigates the dynamics of lock-exchange flows, a particular class of density currents, propagating through rigid emergent vegetation. First, previous mathematical formulation is extended to develop theoretical models of vegetated lock-exchange flows. The regime in which stem drag is inversely proportional to velocity is considered as a special case. Lock-exchange flows were generated in a laboratory flume with rigid cylindrical dowels as model vegetation. Experimental observations were consistent with the theory. Under high stem drag or low stem Reynolds number conditions, the interface deviated from the well-documented block profile associated with unobstructed lock-exchange flows and approached a linear profile. Criteria are developed to categorize all flow conditions as inertial or non-inertial and the interface profile as linear, transitional, or non-linear, respectively, based on (a) the evolution of the velocity of the leading edge of the undercurrent and (b) the interface shape. Finally, the present model is enhanced to account for wind forcing and bed friction to better describe conditions found in nature. The theory highlights the sensitivity of currents to wind forcing.by Yukie Tanino.S.M

Automated extraction of in situ contact angles from micro-computed tomography images of porous media

This material contains work supported by an Aberdeen Formation Evaluation Society student bursary, a Society of Petrophysicist and Well-Log Analysts Foundation grant, and a Messel travel bursary from the Society of Chemical Industry. AI was supported by the University of Aberdeen School of Engineering Elphinstone Ph.D. studentship . The authors gratefully acknowledge Alhammadi et al. (2017) for helpful suggestions on the segmentation and Kamaljit Singh for providing unpublished in situ contact angle measurements (Fig. 11a) for oil ganglion SSa. The authors thank the two anonymous reviewers for their comments.Peer reviewedPostprin

Impact of grain roughness on residual nonwetting phase cluster size distribution in packed columns of uniform spheres

This material contains work supported by an Aberdeen Formation Evaluation Society student bursary and a Society of Petrophysicists and Well Log Analysts Foundation grant. A.I. was supported by the University of Aberdeen School of Engineering Elphinstone Ph.D. studentship. Pore-scale imaging was performed in the Oil & Gas Academy of Scotland x-ray microcomputed tomography facility at University of Aberdeen. The authors thank the two anonymous reviewers for their comments.Peer reviewedPublisher PD

A low-cost, non-hazardous protocol for surface texturing of glass particles

Acknowledgements This material contains work supported by an Aberdeen Formation Evaluation Society student bursary and a Society of Petrophysicists and Well Log Analysts Foundation grant. AI was supported by a University of Aberdeen School of Engineering Elphinstone Ph.D. studentship. Electron microscopy was performed in the ACEMAC Facility at University of Aberdeen; the authors thank John Still for the acquisition of the SEM images. The authors gratefully acknowledge Alfred R. Akisanya and Mark Gourlay for helpful suggestions on the texturing protocol. The authors thank the anonymous reviewer for his/her comments. All data used in this study are available from the corresponding author on reasonable request.Peer reviewedPublisher PD

Model for emergent aquatic plant canopies

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2008.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (p. 159-166).With wetlands constituting about 6% of earth's land surface, aquatic vegetation plays a significant role in defining mean flow patterns and in the transport of dissolved and particulate material in the environment. However, the dependence of the hydrodynamic and transport processes on fundamental properties of an aquatic plant canopy has not been investigated systematically over the wide range of conditions that are observed in the field. A laboratory investigation was conducted to describe flow and solute transport in idealized emergent plant canopies. This thesis presents laboratory measurements of the mean drag, turbulence structure and intensity, and lateral dispersion of passive solute in arrays of randomly-distributed cylinders, a model for emergent, rigid aquatic plants. Mean drag per cylinder length normalized by the mean interstitial fluid velocity and viscosity increases linearly with cylinder Reynolds number. In contrast to the dependence previously reported for sparse arrays at Reynolds numbers greater than 1000, the drag coefficient increases with increasing cylinder density in intermediate and high cylinder densities. In dense arrays, turbulent eddies are constrained by the interstitial pore size such that the integral length scale is equal to the mean surface-to-surface distance between a cylinder in the array and its nearest neighbor. The classic scale model for mean turbulence intensity, which is a function of the inertial contribution to the drag coefficient, the solid volume fraction, and the integral length scale of turbulence normalized by d, is then confirmed with our laboratory measurements. Our laboratory experiments demonstrate that Kyy/ (d), the asymptotic (Fickian) lateral dispersion coefficient normalized by the mean interstitial fluid velocity and d, is independent of Reynolds number at sufficiently high Reynolds number.(cont.) Although previous models predict that asymptotic lateral dispersion increases monotonically with cylinder density, laboratory measurements reveal that lateral dispersion at high Reynolds number exhibits three distinct regimes. In particular, an intermediate regime in which Kyy/ (d) decreases with increasing cylinder density is observed. A scale model for turbulent diffusion is developed with the assumption that only turbulent eddies with integral length scale greater than d contribute significantly to net lateral dispersion. The observed dependence of asymptotic dispersion on cylinder density is accurately described by a linear superposition of this turbulent diffusion model and existing models for dispersion due to the spatially-heterogeneous velocity field that arises from the presence of the cylinders. Finally, laboratory measurements support the conjecture that Kyy/ (d) is not strongly dependent on Reynolds number in dense arrays at any Red. However, the distance required to achieve asymptotic dispersion is shown to depend strongly on the Reynolds number.by Yukie Tanino.Ph.D

Oil/water displacement in microfluidic packed beds under weakly water-wetting conditions : competition between precursor film flow and piston-like displacement

This paper contains work supported by the Royal Society Research Grant RG140009. XZH was supported by the Mexican National Council for Science and Technology, Mexico. The authors gratefully acknowledge Stephen A. Bowden for the absorption spectra (Fig. 3), Bernard Kombe for measuring the permeability of the packed beds and for his contribution to one of the microfluidic experiments, Munasuonyu Walter for the SEM image of crushed marble (Fig. 1) originally published in Bowden et al. 2016, Luca Romanello for providing unpublished viscosity and density measurements from his MSc thesis (Romanello, 2015), Aleksei Gunkin for his insights on post-processing, Paul Hallet for allowing MC access to their tensiometer, and Corex (UK) Ltd. for allowing Luca Romanello and MC access to their viscometer. We thank the three anonymous reviewers for their detailed comments. Open Access via Springer Compact Agreement.Peer reviewedPublisher PD