The Experts below are selected from a list of 75456 Experts worldwide ranked by ideXlab platform
Stephane Zaleski - One of the best experts on this subject based on the ideXlab platform.
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volume of Fluid Interface tracking with smoothed surface stress methods for three dimensional flows
Journal of Computational Physics, 1999Co-Authors: Denis Gueyffier, Ali Nadim, Jie Li, Ruben Scardovelli, Stephane ZaleskiAbstract:Motivated by the need for three-dimensional methods for Interface calculations that can deal with topology changes, we describe a numerical scheme, built from a volume-of-Fluid Interface tracking technique that uses a piecewise-linear Interface calculation in each cell. Momentum balance is computed using explicit finite volume/finite differences on a regular cubic grid. Surface tension is implemented by the continuous surface stress or continuous surface force method. Examples and verifications of the method are given by comparing simulations to analytical results and experiments, for sedimenting droplet arrays and capillary waves at finite Reynolds number. In the case of a pinching pendant drop, both three-dimensional and axisymmetric simulations are compared to experiments. Agreement is found both before and after the reconnections.
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volume of Fluid Interface tracking with smoothed surface stress methods for three dimensional flows
Journal of Computational Physics, 1999Co-Authors: Denis Gueyffier, Ali Nadim, Ruben Scardovelli, Stephane ZaleskiAbstract:Motivated by the need for three-dimensional methods for Interface calculations that can deal with topology changes, we describe a numerical scheme, built from a volume-of-Fluid Interface tracking technique that uses a piecewise-linear Interface calculation in each cell. Momentum balance is computed using explicit finite volume/finite differences on a regular cubic grid. Surface tension is implemented by the continuous surface stress or continuous surface force method. Examples and verifications of the method are given by comparing simulations to analytical results and experiments, for sedimenting droplet arrays and capillary waves at finite Reynolds number. In the case of a pinching pendant drop, both three-dimensional and axisymmetric simulations are compared to experiments. Agreement is found both before and after the reconnections.
Anton P. J. Middelberg - One of the best experts on this subject based on the ideXlab platform.
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reversible active switching of the mechanical properties of a peptide film at a Fluid Fluid Interface
Nature Materials, 2006Co-Authors: Annette F. Dexter, Andrew S. Malcolm, Anton P. J. MiddelbergAbstract:Designer peptides have recently been developed as building blocks for novel self-assembled materials with stimuli-responsive properties. To date, such materials have been based on self-assembly in bulk aqueous solution or at solid-Fluid Interfaces. We have designed a 21-residue peptide, AM1, as a stimuli-responsive surfactant that switches molecular architectures at a Fluid-Fluid Interface in response to changes in bulk aqueous solution composition. In the presence of divalent zinc at neutral pH, the peptide forms a mechanically strong 'film state'. In the absence of metal ions or at acid pH, the peptide adsorbs to form a mobile 'detergent state'. The two interfacial states can be actively and reversibly switched. Switching between the two states by a change in pH or the addition of a chelating agent leads to rapid emulsion coalescence or foam collapse. This work introduces a new class of surfactants that offer an environmentally friendly approach to control the stability of Interfaces in foams, emulsions and Fluid-Fluid Interfaces more generally.
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Reversible active switching of the mechanical properties of a peptide film at a Fluid–Fluid Interface
Nature Materials, 2006Co-Authors: Annette F. Dexter, Andrew S. Malcolm, Anton P. J. MiddelbergAbstract:Designer peptides have recently been developed as building blocks for novel self-assembled materials with stimuli-responsive properties. To date, such materials have been based on self-assembly in bulk aqueous solution or at solid-Fluid Interfaces. We have designed a 21-residue peptide, AM1, as a stimuli-responsive surfactant that switches molecular architectures at a Fluid-Fluid Interface in response to changes in bulk aqueous solution composition. In the presence of divalent zinc at neutral pH, the peptide forms a mechanically strong 'film state'. In the absence of metal ions or at acid pH, the peptide adsorbs to form a mobile 'detergent state'. The two interfacial states can be actively and reversibly switched. Switching between the two states by a change in pH or the addition of a chelating agent leads to rapid emulsion coalescence or foam collapse. This work introduces a new class of surfactants that offer an environmentally friendly approach to control the stability of Interfaces in foams, emulsions and Fluid-Fluid Interfaces more generally.
Ali Nadim - One of the best experts on this subject based on the ideXlab platform.
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volume of Fluid Interface tracking with smoothed surface stress methods for three dimensional flows
Journal of Computational Physics, 1999Co-Authors: Denis Gueyffier, Ali Nadim, Jie Li, Ruben Scardovelli, Stephane ZaleskiAbstract:Motivated by the need for three-dimensional methods for Interface calculations that can deal with topology changes, we describe a numerical scheme, built from a volume-of-Fluid Interface tracking technique that uses a piecewise-linear Interface calculation in each cell. Momentum balance is computed using explicit finite volume/finite differences on a regular cubic grid. Surface tension is implemented by the continuous surface stress or continuous surface force method. Examples and verifications of the method are given by comparing simulations to analytical results and experiments, for sedimenting droplet arrays and capillary waves at finite Reynolds number. In the case of a pinching pendant drop, both three-dimensional and axisymmetric simulations are compared to experiments. Agreement is found both before and after the reconnections.
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volume of Fluid Interface tracking with smoothed surface stress methods for three dimensional flows
Journal of Computational Physics, 1999Co-Authors: Denis Gueyffier, Ali Nadim, Ruben Scardovelli, Stephane ZaleskiAbstract:Motivated by the need for three-dimensional methods for Interface calculations that can deal with topology changes, we describe a numerical scheme, built from a volume-of-Fluid Interface tracking technique that uses a piecewise-linear Interface calculation in each cell. Momentum balance is computed using explicit finite volume/finite differences on a regular cubic grid. Surface tension is implemented by the continuous surface stress or continuous surface force method. Examples and verifications of the method are given by comparing simulations to analytical results and experiments, for sedimenting droplet arrays and capillary waves at finite Reynolds number. In the case of a pinching pendant drop, both three-dimensional and axisymmetric simulations are compared to experiments. Agreement is found both before and after the reconnections.
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tangential stress and marangoni effects at a Fluid Fluid Interface in a hele shaw cell
Joint International Conference on Information Sciences, 1996Co-Authors: Ali Nadim, Ali Borhan, Hossein HajhaririAbstract:Abstract Although the depth-averaged equations describing Fluid flow in a Hele–Shaw cell resemble those of potential flow, the appropriate tangential stress boundary condition at a Fluid–Fluid Interface is different from that for potential flow. The precise form of this boundary condition is derived herein by solving the complete microscale problem near the Interface followed by depth-averaging of the results. The shear stress exerted on the Interface by each phase is found to be proportional to its viscosity, the tangential velocity of the Interface relative to that in the bulk phase, and the reciprocal of a “slip layer” thickness which depends only on the gap width in the Hele–Shaw cell. The results are applied to the problem of translation of a circular drop or bubble in a Hele–Shaw cell, in the presence of Marangoni effects. For instance, the thermocapillary migration velocity of a circular bubble in a constant temperature gradient is found to be inversely proportional to its radius, in contrast with the case of a spherical bubble migrating in an infinite liquid, for which the velocity is directly proportional to the radius.
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Tangential Stress and Marangoni Effects at a Fluid–Fluid Interface in a Hele–Shaw Cell
Journal of Colloid and Interface Science, 1996Co-Authors: Ali Nadim, Ali Borhan, Hossein Haj-haririAbstract:Abstract Although the depth-averaged equations describing Fluid flow in a Hele–Shaw cell resemble those of potential flow, the appropriate tangential stress boundary condition at a Fluid–Fluid Interface is different from that for potential flow. The precise form of this boundary condition is derived herein by solving the complete microscale problem near the Interface followed by depth-averaging of the results. The shear stress exerted on the Interface by each phase is found to be proportional to its viscosity, the tangential velocity of the Interface relative to that in the bulk phase, and the reciprocal of a “slip layer” thickness which depends only on the gap width in the Hele–Shaw cell. The results are applied to the problem of translation of a circular drop or bubble in a Hele–Shaw cell, in the presence of Marangoni effects. For instance, the thermocapillary migration velocity of a circular bubble in a constant temperature gradient is found to be inversely proportional to its radius, in contrast with the case of a spherical bubble migrating in an infinite liquid, for which the velocity is directly proportional to the radius.
Jing Yang - One of the best experts on this subject based on the ideXlab platform.
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microscale pressure measurements based on an immiscible Fluid Fluid Interface
Scientific Reports, 2019Co-Authors: Xing Duan, Andrew K Fraser, Mohammad Ikbal Choudhury, Andrew J Ewald, Jing Yang, Rong LiAbstract:A method of microscale pressure measurement based on immiscible Fluid/Fluid Interface is proposed. This method utilizes observed curvature changes in a Fluid/Fluid Interface, and can accurately report hydraulic pressure in Fluids at length scales of 10 microns. The method is especially suited for measuring Fluid pressure in micro-scale biological samples. Using this method, we probe Fluid pressure build up in epithelial domes, murine mammary gland organoids embedded in hydrogel, and lumen pressure in the developing mouse embryo. Results reveal that the pressure developed across epithelial barriers is on the order of 100~300 Pa, and is modulated by ion channel activity.
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Microscale pressure measurements based on an immiscible Fluid/Fluid Interface.
Scientific Reports, 2019Co-Authors: Jing Yang, Xing Duan, Andrew K Fraser, Mohammad Ikbal Choudhury, Andrew J Ewald, Sean X. SunAbstract:A method of microscale pressure measurement based on immiscible Fluid/Fluid Interface is proposed. This method utilizes observed curvature changes in a Fluid/Fluid Interface, and can accurately report hydraulic pressure in Fluids at length scales of 10 microns. The method is especially suited for measuring Fluid pressure in micro-scale biological samples. Using this method, we probe Fluid pressure build up in epithelial domes, murine mammary gland organoids embedded in hydrogel, and lumen pressure in the developing mouse embryo. Results reveal that the pressure developed across epithelial barriers is on the order of 100~300 Pa, and is modulated by ion channel activity.
Denis Gueyffier - One of the best experts on this subject based on the ideXlab platform.
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volume of Fluid Interface tracking with smoothed surface stress methods for three dimensional flows
Journal of Computational Physics, 1999Co-Authors: Denis Gueyffier, Ali Nadim, Jie Li, Ruben Scardovelli, Stephane ZaleskiAbstract:Motivated by the need for three-dimensional methods for Interface calculations that can deal with topology changes, we describe a numerical scheme, built from a volume-of-Fluid Interface tracking technique that uses a piecewise-linear Interface calculation in each cell. Momentum balance is computed using explicit finite volume/finite differences on a regular cubic grid. Surface tension is implemented by the continuous surface stress or continuous surface force method. Examples and verifications of the method are given by comparing simulations to analytical results and experiments, for sedimenting droplet arrays and capillary waves at finite Reynolds number. In the case of a pinching pendant drop, both three-dimensional and axisymmetric simulations are compared to experiments. Agreement is found both before and after the reconnections.
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volume of Fluid Interface tracking with smoothed surface stress methods for three dimensional flows
Journal of Computational Physics, 1999Co-Authors: Denis Gueyffier, Ali Nadim, Ruben Scardovelli, Stephane ZaleskiAbstract:Motivated by the need for three-dimensional methods for Interface calculations that can deal with topology changes, we describe a numerical scheme, built from a volume-of-Fluid Interface tracking technique that uses a piecewise-linear Interface calculation in each cell. Momentum balance is computed using explicit finite volume/finite differences on a regular cubic grid. Surface tension is implemented by the continuous surface stress or continuous surface force method. Examples and verifications of the method are given by comparing simulations to analytical results and experiments, for sedimenting droplet arrays and capillary waves at finite Reynolds number. In the case of a pinching pendant drop, both three-dimensional and axisymmetric simulations are compared to experiments. Agreement is found both before and after the reconnections.