Frank van Berlo

Eindhoven University of Technology | TUE · Department of Mechanical Engineering

Filament stretching rheometry is a prominent experimental method to determine rheological properties in extensional flow whereby the separating plates determine the extension rate. In literature, several correction factors that can compensate for the errors introduced by the shear contribution near the plates have been introduced and validated in t...

Significance Dispensing of viscoelastic fluids is common in applications like electronic packaging, food engineering, and additive manufacturing. However, viscoelasticity leads to problems like slow liquid bridge breakup, stringiness, and satellite droplets generation. By high-speed imaging and numerical simulation, we show that torsion can break s...

Short liquid bridges are stable under the action of surface tension. In applications like electronic packaging, food engineering and additive manufacturing, this poses challenges to the clean and fast dispensing of viscoelastic fluids. Here, we investigate how short viscoelastic liquid bridges can be destabilized by torsion. We consider a setup con...

A finite element model is presented to describe the flow, resulting stresses and crystal-lization in a filament stretching extensional rheometer (FiSER). This model incorporates nonlinear viscoelasticity, nonisothermal processes due to heat release originating from crystallization and viscous dissipation as well as the effect of crystallization on...