The Marangoni convection describes a flow due to surface tension gradients along free surfaces. The surface tension is a function of the temperature as well as of the composition of the liquid. Therefore, Marangoni convection and the phase change process are closely related.
Marangoni convection, Marangoni induced interfacial deformation and Marangoni instabilities in liquid films determine the performance limits of many heat transfer devices, process engineering plants, plants in the pharmaceutical and food industry, as well as printing and coating processes. For example, the so-called long-wave Marangoni instability leads to film tearing, which considerably impairs the performance of the apparatus and can lead to damage to the apparatus.
The research project “Marangoni in Films” aims at understanding and influencing Marangoni convection, Marangoni-driven film deformation, dynamics and rupture as well as heat and mass transfer. The influence of gravity on Marangoni-driven fluid dynamics and transport processes plays a major role.
Within the scope of the project the experiment “Marangoni in Films”, which is planned for the International Space Station (ISS), will be scientifically accompanied.In parallel, measurement campaigns are carried out in the laboratory and during parabolic flights under reduced gravity. A further component is the performance of numerical simulations to understand the coupled Marangoni induced film flows and transport phenomena and their influence by substrate modification.
The results can be used for the improvement of apparatus and processes in a very wide range of applications, e.g. cooling of electronic components, separation processes in chemical engineering as well as printing and coating processes.