Optimizing Capillary Flows in Twisted Fiber Structures

The transport of drops on slender structures, such as threads and fibers, plays an essential role in engineering applications and is pivotal for the survival of many living creatures. The key to these processes lies in efficiently transporting drops and controlling their motion along the fiber. Drop flow control is enabled by manipulating the fiber’s surface properties, where today’s surface manufacturing methods hinge on advanced and costly techniques, including environmentally harmful chemicals. In the TWIST project, I will develop a new methodology for designing optimal drop transport on twisted fibers and nets. By mechanically twisting multiple fibers with different sizes, geometries, poro-elasticity, and physicochemical properties, I will create, through simple means and without the need for advanced microsystem technology, a hierarchical and grooved structure that can be tuned to control the flow of drops. The TWIST project aims to elucidate the fundamental fluid mechanics of drop capillary flows on these fibrous structures, even when exposed to wind and vibrations, and to provide new theoretical tools for describing the underlying fluid physics. Furthermore, the project will facilitate the development of pathways for utilizing sustainable materials, such as animal and plant-based materials, to generate twisted fiber structures with desired properties and utilize their hygroscopic responses. To showcase its potential use in applications, these fiber structures will be implemented in the fog net technology, which is used to capture atmospheric fog in arid regions. It is envisioned that TWIST will enable new research and engineering a pathways for a Do-It-Yourself solution to produce sustainable threads and nets, going beyond plastic based solutions. If successful, it offers a low-cost sustainable solution relying only on abundant materials found worldwide and can be developed without the need for advanced machining, and as such made by anyone, anywhere.