Modelling of chocolate-specific flushing processes in closed systems

A deciding factor for the success of the German chocolate industry which belongs to the largest producers and exporters of chocolate in Europe and even worldwide is above all the high quality of the manufactured products. Maintaining quality standards with product changes is a key challenge. At present, the governing mechanisms of flushing processes for removing a previous chocolate mass have not been fully understood. Therefore, cleaning processes in closed systems primarily have to be designed using empirical knowledge. The high complexity of the machines and plants and the poor possibilities for monitoring the flushing process contribute to a longer duration of flushing. The use of numerical flow simulation in this context allows for a detailed analysis of the flushing process and enables a more efficient and resource-saving process control.

The aim of the project is to develop an in-depth understanding of the flushing process and to establish a flow simulation model as a tool for the design and optimisation of flushing processes in industrial practice.

The simulation model is based on physical characterisations of the chocolate-specific material and flow properties. Numerical simulations with OpenFOAM and SimulationX are validated by experiments of the Chair of Processing Machines/Processing Technology at TU Dresden, using an industrial test rig with a suitable measuring system. Flushing processes are analyzed for pipes completely filled with chocolate. Further investigations consider partially filled pipes and alternative approaches to designing flushing processes.

© BMWi

This research project is supported by the Industrievereinigung für Lebensmitteltechnologie und Verpackung e. V. (IVLV), the Arbeitsgemeinschaft industrieller Forschungsvereinigungen “Otto von Guericke” e. V. (AiF) and the Federal Ministry of Economic Affairs and Energy (IGF 20672 BR).