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arXiv · 2501.12918

Derivation of a Multiscale Ferrofluid Model: Superparamagnetic Behavior due to Fast Spin Flip

Alexandre Girodoux-Lavigne·Richard M. Höfer
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Abstract

We consider a microscopic model of $N$ magnetic nanoparticles in a Stokes flow. We assume that the temperature is above the critical N\'eel temperature such that the particles' magnetizations undergo random flip with rate $1/\varepsilon$. The microscopic system is the modeled through a piecewise deterministic Markov jump process. We show that for large $N$, small particle volume fraction and small $\varepsilon$, the system can be effectively described by a multiscale model.

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Alexandre Girodoux-Lavigne, Richard M. Höfer. 2025-01-22. Derivation of a Multiscale Ferrofluid Model: Superparamagnetic Behavior due to Fast Spin Flip. https://doi.org/10.2140/paa.2026.8.121

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