Matthys' research is in the general area of Energetics and Fluid/Thermal Sciences, both experimental and numerical. In the Energy field we are conducting work on new concentrated solar thermal systems, bioreactors for algal biodiesel production, and more efficient building HVAC and ship hydrodynamics systems. On the more fundamental side, we are investigating non-Newtonian fluid mechanics and heat transfer, with experimental investigations of the characteristics of complex fluids such as surfactant solutions or polymer solutions, especially turbulent flow of drag-reducing fluids and issues of active control of convective heat transfer. Of interest also are biological fluids and organisms, such as natural marine polymers among others. Studies on implementation of drag-reducing fluids in industrial applications such as HVAC or fluid transport are conducted through laboratory and large-scale field tests. Fundamental rheological work on the equilibrium and dynamic viscoelastic properties of drag-reducing fluids undergoing micellar self-assembly is also a focus of this work. Another area of research is transport phenomena in manufacturing and materials processing, which includes investigations of rapid solidification of molten metals and shape-controlled deposition of organic materials.