Viscoelastic behaviour of fluids in micro-fluidic applications

This PhD project will involve the study and characterization of the rheological, and fluid, dynamic behaviour of viscoelastic fluids in micro-encloses. A large part of the project will be to consider the problem of efficient performance in micro-devices like enhanced mixing or enhanced heat transfer. In order to bypass the limitation of the low Reynolds number which characterizes small scale problems, the basic condition of linearity in low Re Flows is removed by adding flexible, high molecular weight polymers to the working fluid. In these conditions the chaotic motions, typical of turbulent flows, are caused by the elasticity in the fluid (elastic turbulence). A second group of related activities will regard the more general problem of rheological characterization of biological fluids both in vivo or in micro-fluidics devices such as lab-on-chip. The activity will mainly be conducted by numerical simulation using highly accurate methods such as spectral or spectral elements methods. The techniques employed will be particularly challenging since they will require the possibility to reproduce complex rheological behaviours in complex geometries. Experimental validations conducted by partner research groups are also planned.