Christian Clasen
KU Leuven
Chemical Engineer
Fellow, Elected 2024
Christian Clasen obtained his Ph.D. in 2001 from Hamburg University, Germany, under Prof. Dr.-Ing W.-M. Kulicke, focusing on the development of a multi-color pulsed-laser technique for the
rheo-optical investigation of polymer solutions (and beer foams!). He moved to MIT as a postdoctoral researcher with Gareth McKinley where he developed a unique flexure-based
microrheometer for making measurements at very small gaps and with small volumes of biological samples. He returned to Germany in 2003 to pursue his Habilitation at the Institute of
Technical and Macromolecular Chemistry in Hamburg. In 2006 he accepted an offer from KU Leuven, Belgium, to join the Department of Chemical Engineering and he was promoted to full
professor in 2016. He headed the ‘Soft Matter Rheology and Technology (SMaRT)’ division from 2013-21, and is currently the head of the Department of Chemical Engineering, and proud holder
of the golden chalk (‘gouden krijtje’) as the Best Online Teacher in the master’s program of Chemical Engineering.
Clasen’s research focuses on the development of novel experimental tools and high-resolution techniques in the area of rheology and the flow of complex particulate and polymeric fluids. At
MIT he worked on the development and construction of a unique flexure-based microgap rheometer (FMR) that was initially used to study the rheology of biopolymeric liquids such as
spider or silkworm silk, or sundew plant mucilage for which only femtolitre samples were available, as well as structured liquids (emulsions, suspensions and (micro)gels) for which the
length scales of the microstructure and of the flow (i.e. the gap clearance in the sliding plate rheometer) interact. Next generations of the FMR developed at Leuven have been used to control
shearing flows to sub-micrometer level confinements and observe the rheological response of virus particles under confinement by coupling with synchrotron radiation. He has also bridged
this work to the development of tribo-rheological measurement devices and the rheology of lubrication flows. Another area of interest is capillary pinching flows for extensional rheology of
low viscous fluids. Here he has pushed the boundaries for extraction of relaxation times for very dilute solutions, using high speed video imaging analysis down to sub 100μs values. His work on
the non-dimensional representation of capillarity driven flows (colloquially known as the ‘map of misery’) and its extension to liquid-liquid interfaces of Newtonian fluids, as well as more complex
fluids such as semi-dilute polymer solutions and suspensions, has extended our fundamental rheological understanding of these processes and also the range of industrial applications. These
extensions include electrohydrodynamical as well as capillarity- or cavitation-driven creation of nano-filaments and droplets for a variety of controlled release and optoelectronic applications
as well as quantum dot fabrication and nanoparticle encapsulation.