A Novel Binary Particle Fractionation Technique

An interesting development towards a robust particle fractionator is presented. Typically acoustic fractionators rely on time of flight in a constant acoustic field to separate different populations[1,2]. Such a system requires all particles to be concentrated to an initial known point before entering the acoustic field. As the particle population enters the acoustic field, the particles will move towards the nodal point at velocities dictated by their relative size. If the size of the acoustic chamber, flow rates and radiation forces are carefully adjusted, particles can be graded across the width of the chamber when they exit the acoustic field. In this work we describe a technique that allows a more robust fractionation technique which is less sensitive to residence time and allows particle populations to be split in a binary fashion. Modelling results and initial experimental results are presented.