Lubricant-infused surfaces in sUrfactant- and Bacteria-laden turbulent FLOWs

ongoing

Robust surfaces that can resist fouling, reduce flow drag and control heat- and mass transfer in fluctuating flows would have broad technological implications, ranging from biomedical devices and marine industry to food processing and batteries. Slippery surfaces that use microstructures to lock in place a lubricating liquid hold great promise as a breakthrough technology. In gentle conditions, they have already demonstrated anti-fouling, drag reduction and heat-transfer enhancement. However, when submerged in harsh flow environments that contain turbulence, surfactants and microorganisms, these surfaces drastically change their behavior. The lubricant-liquid interface can break up and partially drain resulting in self-emergent surface patterns. It can sustain large capillary waves resulting in surface roughness. It can change or obtain new properties from Marangoni stresses and it can allow the partial attachment of biofilms. Understanding these non-equilibrium states of lubricant-infused surfaces will lead to mitigation of failure modes and to new functionalities of lubricant-infused surfaces, including controlling non-colloidal particles or serving as surface actuators. Therefore, the aim of this project is to provide a deep understanding of lubricant-liquid phenomena in harsh flow environments and lead the way to a new generation of functional surfaces for fluid flows. We will use a unique combination of high-performance computing and flow experiments to untangle the interaction between the tiny scales of liquid-liquid interfaces, large flow patterns, the existence of “hidden” surfactants and the active decisions made by settling bacteria. By establishing the fundamental behavior of lubricant-infused surfaces in dynamic and realistic environments, we pave the way to control transport processes in submerged applications.