Computing the mixing properties of a two-dimensional 'cavity transfer mixer' using a boundary element formulation

From an engineering point of view mixing is one out of few situations where chaos can actually be beneficial to the efficiency of a process. However chaos complicates matters significantly because the process can, and probably will become very sensitive to changes in parameters, meaning that the efficiency of an otherwise good mixing process can decrease considerably when e.g. other fluids are used. Therefore it is very important to have a clear understanding of the major principles of mixing as well as how to optimize the current process. The route towards optimal mixing presented here is based on numerical calculations of velocity fields and particle paths. From these characteristic quantities from dynamical systems analysis are calculated subsequently. Finally they are used to evaluate and reduce the set of adjustable parameters until a 'small' subset of parameters producing good mixing remains.