# A flowing pair of particles in inertial microfluidics.

@article{Schaaf2017AFP, title={A flowing pair of particles in inertial microfluidics.}, author={Christian Schaaf and Felix R{\"u}hle and Holger Stark}, journal={Soft matter}, year={2017}, volume={15 9}, pages={ 1988-1998 } }

A flowing pair of particles in inertial microfluidics gives important insights into understanding and controlling the collective dynamics of particles like cells or droplets in microfluidic devices. They are applied in medical cell analysis and engineering. We study the dynamics of a pair of solid particles flowing through a rectangular microchannel using lattice Boltzmann simulations. We determine the inertial lift force profiles as a function of the two particle positions, their axial…

## 17 Citations

### A pair of particles in inertial microfluidics: effect of shape, softness, and position.

- PhysicsSoft matter
- 2021

This work performs three-dimensional lattice Boltzmann simulations combined with the immersed boundary method to unravel the dynamics of various mono- and bi-dispersed pairs in inertial microfluidics, and shows that stable pairs become unstable when increasing the particle stiffness.

### Particle pairs and trains in inertial microfluidics

- PhysicsThe European Physical Journal E
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Using lattice-Boltzmann simulations, this work thoroughly analyzes the damped displacement pulse traveling as a microfluidic phonon through a staggered train and shows how a defect strongly damps its propagation.

### Optimal Control of Colloidal Trajectories in Inertial Microfluidics Using the Saffman Effect

- BiologyMicromachines
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Using a single optimized control-force protocol, it is demonstrated that even a pulse of particles spread along the channel axis can be steered to a target and that particles of different radii can be separarted most efficiently.

### Numerical investigation of the formation and stability of homogeneous pairs of soft particles in inertial microfluidics

- PhysicsJournal of Fluid Mechanics
- 2022

Abstract We investigate the formation and stability of a pair of identical soft capsules in channel flow under mild inertia. We employ a combination of the lattice Boltzmann, finite element and…

### Lab on a Chip Computational inertial microfluidics: a review †

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Since the discovery of inertial focusing in 1961, numerous theories have been put forward to explain the migration of particles in inertial flows, but a complete understanding is still lacking.…

### Computational inertial microfluidics: a review.

- PhysicsLab on a chip
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This review provides a blueprint for the consideration of numerical solutions for modeling of inertial particle motion, whether deformable or rigid, spherical or non-spherical, and whether suspended in Newtonian ornon-Newtonian fluids.

### Solid particles moving parallel to a deformable liquid–liquid interface in a micro-channel: migration forces

- PhysicsJournal of Fluid Mechanics
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Abstract This work focuses on the dynamics of a train of solid particles, separated by a distance $L$, flowing near a deformable interface formed by two co-flowing immiscible fluids in a microchannel…

### Steady State of Motion of Two Particles in Poiseuille Flow of Power-Law Fluid

- EngineeringPolymers
- 2022

The steady state of motion of two particles in Poiseuille flow of power-law fluid is numerically studied using the lattice Boltzmann method in the range of Reynolds number 20 ≤ Re ≤ 60, diameter…

## References

SHOWING 1-10 OF 56 REFERENCES

### Feedback control of inertial microfluidics using axial control forces.

- PhysicsLab on a chip
- 2014

This work determined the equilibrium positions in square and rectangular cross sections and classify their types of stability for different Reynolds numbers, particle sizes, and channel aspect ratios and demonstrated how an axial control force slows down the particles and shifts the stable equilibrium position towards the channel center.

### Pairwise interactions in inertially driven one-dimensional microfluidic crystals

- PhysicsPhysical Review Fluids
- 2018

In microfluidic devices, inertia drives particles to focus on a finite number of inertial focusing streamlines. Particles on the same streamline interact to form one-dimensional microfluidic crystals…

### Inertial microfluidics with multi-particle collision dynamics

- PhysicsThe European physical journal. E, Soft matter
- 2012

This work investigates inertial focussing in microfluidic channels that gives rise to the Segré-Silberberg effect and introduces a Langevin equation for the cross-sectional motion whose steady state is the Boltzmann distribution that contains the integrated lift force as potential energy.

### Controlling inertial focussing using rotational motion

- PhysicsThe European physical journal. E, Soft matter
- 2014

This work controls the rotational motion of a particle and demonstrates that this allows to manipulate the lift-force profile and thereby the particle's equilibrium positions, and performs two-dimensional simulation studies using the method of multi-particle collision dynamics.

### Optimal control of particle separation in inertial microfluidics

- Engineering, PhysicsThe European physical journal. E, Soft matter
- 2013

This article uses a theoretical study to demonstrate how concepts from optimal control theory help to design optimized profiles of control forces that allow to steer particles to almost any position at the outlet of a microfluidic channel.

### Inertial migration of a rigid sphere in three-dimensional Poiseuille flow

- PhysicsJournal of Fluid Mechanics
- 2015

Abstract Inertial lift forces are exploited within inertial microfluidic devices to position, segregate and sort particles or droplets. However, the forces and their focusing positions can currently…

### Fundamentals and applications of inertial microfluidics: a review.

- PhysicsLab on a chip
- 2016

This review discusses the fundamental kinematics of particles in microchannels to familiarise readers with the mechanisms and underlying physics in inertial microfluidic systems and presents a comprehensive review of recent developments and key applications of inertialMicrofluidics systems according to their microchannel structures.

### Inertial migration and axial control of deformable capsules.

- BiologySoft matter
- 2017

This work performs hydrodynamic simulations based on the lattice-Boltzmann method and study the behavior of an elastic capsule in a microfluidic channel flow in the inertial regime, finding that this equilibrium distance is nearly independent of the channel Reynolds number and falls on a single master curve when plotted versus the Laplace number.

### Dynamic self-assembly and control of microfluidic particle crystals

- EngineeringProceedings of the National Academy of Sciences
- 2010

Focusing on the dynamics of the particle–particle interactions reveals a mechanism for the dynamic self-assembly process; inertial lift forces and a parabolic flow field act together to stabilize interparticle spacings that otherwise would diverge to infinity due to viscous disturbance flows.

### Nonlinear dynamics of spherical particles in Poiseuille flow under creeping-flow condition.

- Mathematics, PhysicsThe Journal of chemical physics
- 2013

The nonlinear dynamics of spherical colloids under the influence of a pressure driven flow at vanishing Reynolds number is studied and how the results help to understand the stability of particle trains composed of several particles is discussed.