Topic 3. Heterogeneous systems, interfaces, system-boundaries, and small systems

The flow of blood through narrow capillaries, the multiphase flow in porous rocks encountered in tertiary oil recovery, or the foam and emulsions we find in food, pharmaceutical, or cosmetic products, are just a few examples of highly heterogeneous systems, in which internal interfaces or system boundaries have a dominant effect on the overall dynamics of the system. The aim of this section is to discuss recent progress in the modeling of these systems with nonequilibrium thermodynamics. Examples of topics which may be included here are:

• Contributions focusing on modeling the behavior of heterogeneous systems with deformable internal interfaces, within frameworks such as the Gibbs dividing surface or the diffuse interface model. Topics of interest here are, for example, constitutive modeling of surface rheology, mass, and momentum transfer, or the coupling of bulk and interfacial behavior.
• The effects of rigid and deformable system boundaries on multiphase flows.
• Contributions in the field of dynamic systems which are heterogeneous on the nanoscale, particularly relevant in view of the recent advent in nanotechnology. Here the traditional formulations for bulk phase behavior break down, and we have to resort to dynamic extensions of Terrell Hill's thermodynamics of small systems.

Other abstracts which discuss topics not listed here, but which are within the scope of this section will also be considered.

Teachers (Summer school)

• Dick Bedeaux   Norwegian University of Science and Technology - Trondheim, Norway
• Leonard Sagis   Wageningen University, The Netherlands

Topic organizers

• Dick Bedeaux   Norwegian University of Science and Technology - Trondheim, Norway
• Leonard Sagis   Wageningen University, The Netherlands

2025