Migration of twisted ribbon-like particles in simple shear flow

The motion of rigid twisted ribbon-like particles in shear flow is studied by computer simulation. It is shown that the twisted ribbon migrates in the vorticity direction in strong shear flow with the sign determined by the chirality: the right-handed particles and their mirror-imaged particles move in opposite directions. This enables the separation of chiral particles from the racemic mixture. The average migration velocity in the vorticity direction is studied as a function of the shear rate, the length, and the pitch of the particle. (c) 2005 American Institute of Physics.