Wednesday, October 17, 2012 - 4:15pm
Jenny Wagner (Heidelberg Collaboratory for Image Processing):
"Simulation and selective deposition of microparticles in electrical fields"
Abstract. Observing the paths of cosmic dust in space can give valuable information on star formation. When cosmic dust reaches a detector, astronomers can solve an inverse problem to determine its origin and, knowing the initial conditions, can even specify the interaction processes on its way. Similar to that I investigated the behaviour of negatively charged microparticles in an electrical field for a biophysical application: microparticles with radii of 2-5 micrometers were triboelectrically charged and dispensed in an aeorol. The two-phase flow consisting of the solid particles and the pressurised air was then exposed to a programmable electrical field pattern, such that the aerosol and the electrical forces guided the particles to previously determined locations in the detection plane.While astronomers are interested in the description of particle trajectories and interactions, my goal was to model this particle deposition to understand the behaviour of the particles in different electrical fields and to find the optimum setup configuration and particle parameters, such that all particles reach their respective deposition locations and none are incorrectly deposited. In my talk I will describe the modelling process of the two phase flow and the experimental constraints, as well as the results obtained in the subsequent simulations using COMSOL multiphysics.