Driven mixtures of colloid particles in micropores

Abstract:

In microfluidic structures we typically encounter multiphase flow. Among them, colloid suspensions appear in many technological as well as biophysical applications. In this talk we report on theoretical modelling of the situation in which mixture of spherical particles of various sizes flows through microfluidic channel of modulated profile. The focus of the work is at the possibility and efficiency of separation of particles according to their size. In the first part of the talk we show how the inertial hydrodynamic effects, mostly neglected so far, are in fact crucial for interpretation of experiments on hydrodynamic ratchets. In the second part, we present our approach to dense mixtures, using newly formulated hydrodynamic approximation for mixed driven lattice gasses. We shall list the cases in which analytical solution is possible. In generic situation, the numerical solution of the set of PDEs is compared with direct stochastic simulation.