Cross-stream migration of non-spherical particles in a second-order fluid – theories of particle dynamics in arbitrary quadratic flows

Tai, Cheng-Wei; Wang, Shiyan; Narsimhan, Vivek

doi:10.1017/jfm.2020.300

Cited by 14 publications

(28 citation statements)

References 41 publications

(47 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…with D Dt = ∂ ∂t + u i i and torque T p i on the particle that are exact in the limit of ψ 1 = − 2ψ 2 27 :…”

Section: Theories On Arbitrary-shaped Particle Dynamics In a Generamentioning

confidence: 99%

“…The time unsteadiness of the polymeric effects appear at a higher-order (O (Wi 2 )). 25,27 With Equations (6) and (7), we will be able to calculate the polymeric force and torque on a particle once we have the information on the flow profile and the force moments on the particle in a Stokes flow. Note that these solutions are valid for arbitrarily-shaped particles and any flow profile up to quadratic order with the assumption of 27 We note that for a general polymeric solution, ψ 1 is typically found to be 6-7 times larger than ψ 2 in magnitude.…”

Section: Theories On Arbitrary-shaped Particle Dynamics In a Generamentioning

confidence: 99%

“…25,27 With Equations (6) and (7), we will be able to calculate the polymeric force and torque on a particle once we have the information on the flow profile and the force moments on the particle in a Stokes flow. Note that these solutions are valid for arbitrarily-shaped particles and any flow profile up to quadratic order with the assumption of 27 We note that for a general polymeric solution, ψ 1 is typically found to be 6-7 times larger than ψ 2 in magnitude. 29 Although the assumption ψ 1 = − 2ψ 2 overestimates the effect of ψ 2 , the solution nevertheless provides us a simple way to gain qualitative insight into the orientation dynamics and migration behavior of these nonspherical particles.…”

Section: Theories On Arbitrary-shaped Particle Dynamics In a Generamentioning

confidence: 99%

“…17 D'Avino et al (2019) numerically studied the dynamics of a spheroidal particle in a pressure-driven slit flow with a finite channel cross section, using Giesekus constitutive model. 26 For more systematic studies, our recent theoretical work 27 developed approximate, analytical solutions to the polymeric force/torque on a rigid, arbitrary-shaped particle in a general quadratic flow of secondorder fluid under the assumption of ψ 1 = − 2ψ 2 (co-rotational limit), where ψ 1 and ψ 2 are the first and second normal stress coefficients that monitor the normal stress differences in flow-shear gradient direction and shear gradient-vorticity direction, respectively. We find that the particle migration velocity is directly proportional to the length spanned by the particle in the shear gradient direction of the flow.…”

Section: Introductionmentioning

confidence: 99%

“…This orientation mode, so called log-rolling motion, leads to a shorter span in the shear-gradient direction and thus slower overall migration compared with a sphere of equal volume. 27 This observation motivated us to explore the possibility of manipulating the particle migration using different flow profiles. For instance, a circular tube flow profile with velocity curvature in all radial directions could possibly suppress the log-rolling motion of orientable particles, and therefore fundamentally alter their migration trajectories.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Cross‐stream migration of nonspherical particles in second‐order fluid flows: Effect of flow profiles

2020

Self Cite

View full text Add to dashboard Cite

We investigate the cross-stream migration of spheroidal particles in a weakly viscoelastic fluid under various unbound parabolic flows (circular and elliptic tube flow, as well as 2D slit flow). The viscoelastic fluid investigated is a second-order fluid under the co-rotational limit. Our theory finds that the different flow profiles do not significantly alter the migration speed of particles toward the flow centerline, but drastically alter their orientation dynamics. At long times, prolate particles align along the flow direction in a circular tube flow, but undergo log-rolling in a 2D slit flow. We explain the origin of these orientation dynamics, and explain why such behavior can give rise to a similar cross-stream migration velocity. We lastly examine particle motion in an unbound elliptic tube flow with unequal velocity curvature in the two lateral directions. We quantify the conditions under which the long-time particle orientation changes from log-rolling to flow-alignment.

show abstract

“…with D Dt = ∂ ∂t + u i i and torque T p i on the particle that are exact in the limit of ψ 1 = − 2ψ 2 27 :…”

Section: Theories On Arbitrary-shaped Particle Dynamics In a Generamentioning

confidence: 99%

Section: Theories On Arbitrary-shaped Particle Dynamics In a Generamentioning

confidence: 99%

Section: Theories On Arbitrary-shaped Particle Dynamics In a Generamentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Cross‐stream migration of nonspherical particles in second‐order fluid flows: Effect of flow profiles

2020

Self Cite

View full text Add to dashboard Cite

show abstract

On the behavior of prolate spheroids in a standing surface acoustic wave field

Sachs,

Schmidt,

Cierpka

et al. 2023

Microfluid Nanofluid

View full text Add to dashboard Cite

The active manipulation of particle and cell trajectories in fluids by high-frequency standing surface acoustic waves (sSAW) allows to separate particles and cells systematically depending on their size and acoustic contrast. However, process technologies and biomedical applications usually operate with non-spherical particles, for which the prediction of acoustic forces is highly challenging and remains a subject of ongoing research. In this study, the dynamical behavior of prolate spheroids exposed to a three-dimensional acoustic field with multiple pressure nodes along the channel width is examined. Optical measurements reveal an alignment of the particles orthogonal to the pressure nodes of the sSAW, which has not been reported in literature so far. The dynamical behavior of the particles is analyzed under controlled initial conditions for various motion patterns by imposing a phase shift on the sSAW. To gain detailed understanding of the particle dynamics, a three-dimensional numerical model is developed to predict the acoustic force and torque acting on a prolate spheroid. Considering the acoustically induced streaming around the particle, the numerical results are in excellent agreement with experimental findings. Using the proposed numerical model, a dependence of the acoustic force on the particle shape is found in relation to the acoustic impedance of the channel ceiling. Hence, the numerical model presented herein promises high progress for the design of separation devices utilizing sSAW, exploiting an additional separation criterion based on the particle shape.

show abstract

On the some issues of particle motion in the flow of viscoelastic fluids

Lin

2022

Acta Mech. Sin.

View full text Add to dashboard Cite

Cross-stream migration of non-spherical particles in a second-order fluid – theories of particle dynamics in arbitrary quadratic flows

Cited by 14 publications

References 41 publications

Cross‐stream migration of nonspherical particles in second‐order fluid flows: Effect of flow profiles

Cross‐stream migration of nonspherical particles in second‐order fluid flows: Effect of flow profiles

On the behavior of prolate spheroids in a standing surface acoustic wave field

On the some issues of particle motion in the flow of viscoelastic fluids

Contact Info

Product

Resources

About