Investigation of the Temperature Distribution in Co-Rotating Twin-Screw Extruders

Intermeshing extruders are most commonly used in the polymer and food industries, but lately the importance of extrusion in the pharmaceutical industry is increasing related to the production of solid drug products. Although extruders have been used for decades, the process of extrusion is not well understood yet. Simulations are not routinely carried out because of the complex intermeshing geometry of the screw elements. Common simulations approaches are struggling with the intermeshing region of the screws. Moreover, it is also difficult to predict the shape of the free surface in partially filled regions. Since Smoothed Particle Hydrodynamics (SPH) can handle moving and intermeshing boundaries and also predict free surfaces it is a promising modeling approach. Compared to regular mesh-based CFD methods, such as FVM, SPH cannot handle complex wall boundaries properly. To overcome this difficulty a potential-based wall interaction model has been previously developed. Based on this work hot melt extrusion was investigated by calculating the temperature distribution in Co-Rotating Twin-Screw Extruders using SPH
as the modeling approach to get a deeper understanding of the HME process and therefore contribute to possible scale up techniques or screw design optimisations. Since hot melt extrusion has the potential to solve problems related to poorly soluble drug molecules via amorphous solid dispersion formation, this work is significant for the pharmaceutical industry.