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1. Liquid Flow Patterns and Particle Settling Velocity in a Taylor-Couette Cell Using Particle Image Velocimetry and Particle Tracking Velocimetry

   https://doi.org/10.2118/219459-PA  

   Velez, Andres F; Kalaga, Dinesh V; Kawaji, Masahiro Kawaji (February 2024, SPE Journal)

   Controlling the downhole pressure is an important parameter for successful and safe drilling operations. Several types of weighting agents (i.e., high-density particles), traditionally barite particles, are added to maintain the desired density of the drilling fluid (DF). The DF density is an important design parameter for preventing multiple drilling complications. These issues are caused by the settling of the dense particles, an undesired phenomenon also referred to as sagging. Therefore, there is a need to understand the settling characteristics of heavy particles in such scenarios. To this end, simultaneous measurements of liquid phase flow patterns and particle settling velocities have been conducted in a Taylor-Couette (TC) cell with a rotating inner cylinder and stationary outer cylinder separated by an annular gap of 9.0 mm. Liquid flow patterns and particle settling velocities have been measured using particle image velocimetry (PIV) and particle tracking velocimetry (PTV) techniques, respectively. Experiments have been performed by varying the rotational speed of the inner cylinder up to 200 rev/min, which is used in normal drilling operations. Spherical particles with diameters of 3.0 mm or 4.0 mm and densities between 1.2 g/cm3 and 3.95 g/cm3 were used. The liquid phases studied included deionized (DI) water and mineral oil, which are the basic components of a non-Newtonian DF with a shear-thinning viscosity. The DF is a mud-like emulsion of opaque appearance, which impedes the ability to observe the liquid flow field and particle settling in the TC cell. To address this issue, a solution of carboxymethyl cellulose (CMC) with a 6% weight concentration in DI water was used. This non-Newtonian solution displays shear-thinning rheological behavior and was used as a transparent alternative to the opaque DF. For water, PIV results have shown wavy vortex flow (WVF) to turbulent Taylor vortex flow (TTVF), which agrees with the flow patterns reported in the literature. For mineral oil, circular Couette flow (CCF) was observed at up to 100 rev/min and vortex formation at 200 rev/min. For CMC, no vortex formation was observed up to 200 rev/min, only CCF. The settling velocities for all particles in water matched with the particle settling velocities predicted using the Basset-Boussinesq-Oseen (BBO) equation of motion. For mineral oil and CMC, the results did not match well with the predicted settling velocities, especially for heavy particles due possibly to the radial particle migration and interactions with the outer cylinder wall. 

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2. Microscale, scanning defocusing volumetric particle-tracking velocimetry

   https://doi.org/10.1007/s00348-019-2731-4  

   Guo, Tianqi; Ardekani, Arezoo M.; Vlachos, Pavlos P. (June 2019, Experiments in Fluids)
3. Volumetric particle tracking velocimetry (PTV) uncertainty quantification

   https://doi.org/10.1007/s00348-020-03021-6  

   Bhattacharya, Sayantan; Vlachos, Pavlos P. (September 2020, Experiments in Fluids)
4. PREDICTING NEAR-BED SEDIMENT TRANSPORT THROUGH PARTICLE IMAGE VELOCIMETRY

   https://doi.org/10.9753/icce.v37.papers.9  

   Hoch, Caroline; Weaver, Robert J; Webb, Bret; Resio, Don; Ward, Nikole; Lodge, Caleb; Hopkin, Olivia; Bouhassira, Ruby; Kachouie, Nezamoddin N (September 2023, Coastal Engineering Proceedings)

   Coastal communities are growing globally, promoted by the ocean’s abundant opportunity for food, recreation, tourism, and green energy. Erosion and accretion along the coast significantly affect the safety of these communities and longevity of coastal infrastructure. To better predict rates of erosion and accretion, sediment transport models and active-bed thickness prediction techniques are of particular importance. Two dimensionless parameters, the Shields and Ursell parameters, are often used to predict rates of sediment transport and wave linearity. The goal of this project is to analyze sediment movement in a laboratory wave flume using particle image velocimetry (PIV). From the analysis we estimate the dimensionless parameters and instantaneous active-bed thickness to predict volumetric sediment transport rates as waves propagate shoreward. 

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5. Remote Sensing of Riverbank Migration Using Particle Image Velocimetry

   https://doi.org/10.1029/2023JF007177  

   Chadwick, Austin J.; Greenberg, Evan; Ganti, Vamsi (July 2023, Journal of Geophysical Research: Earth Surface)

   Abstract Mobile river channels endanger human life and property and over centuries shape ecosystems, landscapes, and stratigraphy. Quantifying channel movements from remote sensing is difficult, in part due to the diversity of river mobility processes (e.g., channel migration, cutoffs, avulsion) and planform morphologies (e.g., meandering, braided). Here, we present a framework for quantifying riverbank migration from remote sensing that upscales recent methodological advances from laboratory flume studies utilizing particle image velocimetry (PIV). We apply PIV to image time series of 21 rivers worldwide, showing PIV ignores cutoff and avulsion processes by design and is well suited for tracking riverbank migration regardless of planform morphology. We show that PIV‐derived results for riverbank migration are consistent with published results from centerline‐ and bank‐based Lagrangian methods. Unlike existing methods, PIV offers a grid‐based Eulerian framework where defining channel centerlines is unnecessary and quantified uncertainty in riverbank positions is propagated into uncertainty in migration rates. PIV offers means to efficiently extract global patterns in riverbank migration from decades of satellite data, as well as investigate river response to climate change and human activities in our rapidly changing world. 

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