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arXiv · 2409.12488

Dense Suspension Inertial Microfluidic Particle Theory (DENSE-IMPACT) Model for Elucidating Outer Wall Focusing at High Cell Densities

Soon Wei Daniel Lim·Yong How Kee·Scott Nicholas Allan Smith·Shan Mei Tan·An Eng Lim·Yuansheng Yang·Shireen Goh
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Abstract

Inertial microfluidics has been limited to dilute particle concentrations due to defocusing (spreading out) at high particle concentrations. We observe a counterintuitive shift of focusing to the outer curved wall under high concentration flow, which contradicts the existing particle focusing theory. We developed a multiphase model incorporating lift forces and particle-particle interactions to explain this behaviour. Numerical simulations validated by experimental data reveal the shift is governed by the ratio of the lift force strength to that of particle interaction frequencies.

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Soon Wei Daniel Lim, Yong How Kee, Scott Nicholas Allan Smith, Shan Mei Tan, An Eng Lim, Yuansheng Yang, Shireen Goh. 2024-09-19. Dense Suspension Inertial Microfluidic Particle Theory (DENSE-IMPACT) Model for Elucidating Outer Wall Focusing at High Cell Densities. https://arxiv.org/abs/2409.12488

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