Mathematical modelling and simulation of dispersive mixing

Rubber and plastics companies are using mixing equipment ('internal mixers') which was invented by Banbury in 1916 and which has hardly evolved since then. There is an urgent need for the modernization of such equipment and the market is demanding higher and higher performances for rubber goods. The physics of the dispersion of porous or fibrous agglomerates in a flow field has not been widely addressed in the past, despite of its importance. This is mainly due to the technical difficulties associated with the observations of the kinetics of this disagglomeration and the wide range of size that must be probed. Two mechanisms are recognized : erosion and rupture. Actually, different software solutions to simulate the 3D transient behavior of a flow in internal batch mixer are available. In all existing codes, it is assumed that mixing and flow calculations are decoupled : the analysis of the mixing (distributive or dispersive mixing) is performed after the calculation of the flow. To sum-up, hierarchical modeling including micro-macro models is considered in this work. In this thesis, we developed new distributive tools and new dispersive mathematical model. We compared the numerical prediction with several experiments. Finally, we use this model to design a new rotor shape in the framework of a European project.(FSA 3)--UCL, 200