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arXiv · 1401.7311

Flow pattern in the vicinity of self-propelling hot Janus particles

Thomas Bickel·Arghya Majee·Alois Würger
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Abstract

We study the temperature field and the resulting flow pattern in the vicinity of a heated metal-capped Janus particle. If its thickness exceeds about 10 nm, the cap forms an isotherm and the flow pattern comprises a quadrupolar term that decays with the square of the inverse distance 1/r^2. For much thinner caps the velocity varies as 1/r^3. These findings could be relevant for collective effects in dense suspensions and for the circular tracer motion observed recently in the vicinity of a tethered Janus particle.

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Thomas Bickel, Arghya Majee, Alois Würger. 2014-01-28. Flow pattern in the vicinity of self-propelling hot Janus particles. https://doi.org/10.1103/physreve.88.012301

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