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arXiv · 2012.06190

Lattice Boltzmann simulations on the tumbling to tank-treading transition: effects of membrane viscosity

Fabio Guglietta·Marek Behr·Luca Biferale·Giacomo Falcucci·Mauro Sbragaglia
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Abstract

The tumbling to tank-treading (TB-TT) transition for red blood cells (RBCs) has been widely investigated, with a main focus on the effects of the viscosity ratio $\lambda$ (i.e., the ratio between the viscosities of the fluids inside and outside the membrane) and the shear rate $\dot{\gamma}$ applied to the RBC. However, the membrane viscosity $\mu_m$ plays a major role in a realistic description of RBC's dynamics, and only a few works have systematically focused on its effects on the TB-TT transition. In this work, we provide a parametric investigation on the effect of membrane viscosity $\mu_m$ on the TB-TT transition, for a single RBC. It is found that, at fixed viscosity ratios $\lambda$, larger values of $\mu_m$ lead to an increased range of values of capillary number at which the TB-TT transition occurs. We systematically quantify such an increase by means of mesoscale numerical simulations based on the lattice Boltzmann models.

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Fabio Guglietta, Marek Behr, Luca Biferale, Giacomo Falcucci, Mauro Sbragaglia. 2020-12-11. Lattice Boltzmann simulations on the tumbling to tank-treading transition: effects of membrane viscosity. https://doi.org/10.1098/rsta.2020.0395

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