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Abstract Insulator‐based dielectrophoretic (iDEP) microdevices have been limited to work with Newtonian fluids. We report an experimental study of the fluid rheological effects on iDEP focusing and trapping of polystyrene particles in polyethylene oxide, xanthan gum, and polyacrylamide solutions through a constricted microchannel. Particle focusing and trapping in the mildly viscoelastic polyethylene oxide solution are slightly weaker than in the Newtonian buffer. They are, however, significantly improved in the strongly viscoelastic and shear thinning polyacrylamide solution. These observed particle focusing behaviors exhibit a similar trend with respect to electric field, consistent with a revised theoretical analysis for iDEP focusing in non‐Newtonian fluids. No apparent focusing of particles is achieved in the xanthan gum solution, though the iDEP trapping can take place under a much larger electric field than the other fluids. This is attributed to the strong shear thinning‐induced influences on both the electroosmotic flow and electrokinetic/dielectrophoretic motions.
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Data for: Anomalous crystalline ordering of particles in a viscoelastic fluid under high shear
This dataset is for the following study: Anomalous crystalline ordering of particles in a viscoelastic fluid under high shear by Sijie Sun, Nan Xue, Stefano Aime, Hyoungsoo Kim, Jizhou Tang, Gareth H. McKinley, Howard A. Stone, and David A. Weitz. In this research, the authors investigate the high-shear-rate behavior of particle suspensions in viscoelastic fluids using a fully immersed parallel plate geometry. They discover an unexpected particle separation within the suspension, leading to the formation of a crystalline layer in the center of the cell. This solid layer disrupts the flow instability and introduces a new single-frequency component to the torque fluctuations, reflecting a dominant velocity pattern in the flow. The findings reveal the complex interplay between particles and the suspending viscoelastic fluid under extreme shear conditions. The SI videos, raw data and code of postprocessing are included
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- Award ID(s):
- 2011754
- PAR ID:
- 10501543
- Publisher / Repository:
- Harvard Dataverse
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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