Dresden 2006 – wissenschaftliches Programm
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CPP: Chemische Physik und Polymerphysik
CPP 22: SYMPOSIUM Microfluidics II: Soft objects in flow, open geometries
CPP 22.8: Vortrag
Donnerstag, 30. März 2006, 16:30–16:45, ZEU 160
Ratchet driven microfluidic transport — •Karin John1 and Uwe Thiele1,2 — 1Max-Planck-Institut für Physik komplexer Systeme, Nöthnitzer Str. 38, D-01187 Dresden, Germany — 2Lab. Spectrometrie Physique, Univ. J. Fourier - Grenoble I, 140 Av. Physique, 38402 Saint-Martin d’Heres, France
Transport in spatially extended systems can be induced if nonequilibrium fluctuations and a broken spatial symmetry are present [1]. This can be realized using a global gradient or a globally homogeneous system that displays local time-periodic asymmetries, e.g., a flashing periodic asymmetric potential (ratchet). Examples where a diffusive transport is induced are molecular motors [2] or the particle transport through asymmetric pores [3].
We propose a concept for ratchet driven open microfluidic flow, i.e. involving liquid with a free surface, like droplets and films. After introducing the basic principle, a theoretical model in long-wave approximation [4] is presented. It is used to analyse the ratchet-driven convective transport in detail.
[1] R. D. Astumian, Science 276, 917–922 (1997).
[2] F. Jülicher, A. Ajdari, A. and J. Prost, Rev. Mod. Phys. 69, 1269–1281 (1997).
[3] S. Matthias and F. Müller, F., Nature 424, 53-57 (2003).
[4] A. Oron, S. H. Davis and S. G. Bankoff, Rev. Mod. Phys. 69, 931-980 (1997).