I Professori Miroslav Bulíček e Josef Málek, dell’Istituto di Matematica della Charles University, Praga, il giorno 14 giugno 2018, dalle ore 14.30, nell’aula F del Dipartimento di Matematica e Fisica, terranno i seguenti seminari

«PDE analysis of a class of thermodynamically compatible viscoelastic compressible and incompressible rate-type fluids with stress-diffusion»

Miroslav Bulíček

Abstract. We present a system of PDEs governing the motion of non-Newtonian fluids described by a simplified viscoelastic rate-type model with a stress-diffusion term. The simplified model shares many qualitative features with more complex viscoelastic rate-type models that are frequently used in the modeling of fluids with complicated microstructure. As such, the simplified model provides important preliminary insight into the mathematical properties of these more complex and practically relevant models of non-Newtonian fluids. The simplified model that is analyzed from the mathematical perspective is shown to be thermodynamically consistent, and we extensively comment on the interplay between the thermodynamical background of the model and the mathematical analysis of the corresponding initial-boundary-value problem. Furthermore, we will show how the result can be extended to the non-simplified setting.

« Towards complex/structured fluids»

Josef Málek

Abstract. Most fluid-like substances, such as geomaterials, bio fluids and polymeric liquids, are complex fluids exhibiting intricate nonlinear rheological response and structures. The aim of the talk is to present unified novel viewpoints how to describe the responses of such materials. A particular attention will be devoted to the mechanical and thermodynamical underpinnings of the considered models and their consequences towards the long-time and large-data existence of generalized (weak) solutions of relevant initial and boundary value problems.

Proponenti:

Prof.ssa Francesca Crispo

Prof. Paolo Maremont