Offer Description
Processes such as hot-melt extrusion (HME) and twin-screw melt granulation (TSMG) are widely used in the pharmaceutical industry to continuously produce high value-added products. In HME, a powdered mixture containing the drug and an appropriate polymer is processed to form an amorphous solid dispersion with improved drug solubility. In contrast, the TSMG process uses a molten polymer as a binder to convert fine drug powders into larger, more manageable granules.
In both cases, powdered materials—exposed to elevated temperatures and shear forces—undergo partial or complete transformation from the crystalline to the amorphous state. Optimization of these processes is often based on a trial-and-error approach due to the complex interactions between processing conditions (e.g., temperature, shear profile, feed rate, and residence-time distribution) and material attributes (drug–polymer compatibility, particle-surface properties, particle-size distribution, shape, and others).
The main goal of this project is to extend our experimental work by integrating modelling approaches to better predict powder behavior during feeding and processing. By combining particle-level surface-property characterization with discrete element method (DEM) simulations, we aim to model powder flow in the early stages of HME and during TSMG. Particle contact mechanics (e.g., parameter of the JKR particle adhesion model) will be adjusted according to the process conditions—particularly based on the temperature profiles—to reflect increasing adhesion between polymer and drug particles.
For HME, DEM simulations of the initial section of the extruder will be coupled with computational fluid dynamics (CFD) simulations of the molten material in the downstream section, incorporating experimentally measured rheological properties. This multiscale modelling approach will allow us to simulate both HME and TSMG and evaluate how operating parameters (e.g., screw speed, temperature settings, screw configuration) influence final material characteristics such as homogeneity.
Simulation outcomes will be combined with experimental data collected by other PhD students to develop a comprehensive 3D model of both TSMG and HME processes. Once established, this model will support scale-up to pilot-scale equipment, where simulation predictions will be validated against experimental runs. In the final project stage, the model will be used to characterize shear-stress distribution along the extruder barrel, barrel-filling behavior, material homogeneity, and other key process indicators.
Where to apply
E-mail: miroslav.soos@vscht.cz
Requirements
Research Field: Engineering » Chemical engineering
Education Level: Master Degree or equivalent
Research Field: Engineering » Mechanical engineering
Education Level: Master Degree or equivalent
Research Field: Engineering » Materials engineering
Education Level: Master Degree or equivalent
Skills/Qualifications: Suitable candidate is familiar with modeling concept of particle flow or modelling of melt flow, has knowledge of numerical methods used for such simulations (i.e., CFD, DEM, SPH). Hands-on experience with powder flow characterization will be an asset.
Languages: ENGLISH
Level: Good
Additional Information
Work Location(s)
Number of offers available: 1
Company/Institute: University of Chemistry and Technology Prague
Country: Czech Republic
City: Prague
Postal Code: 16628
Street: Technicka 3
Contact
City: Prague
Website: https://beamlab.vscht.cz/
Street: Technicka 5
Postal Code: 166 28
E-Mail: miroslav.soos@vscht.cz
Phone: 220443251
