(414c) Fluid Instabilities for Thermoregulatory Homeostasis

Emerging pattern dynamics in natural systems – those underlying the structure of snowflake crystals, bacterial colonies, microorganisms, and retinal vessels – have fascinated scientists for decades. These highly useful morphologies evolve when systems are driven to instability, far from equilibrium.

In this talk, I will discuss our recent efforts to harness unstable pattern dynamics to develop self-regulating energy materials that address one of our largest sustainability challenges of the day: keeping humans comfortable. Specifically, I will explain how to exploit the Saffman-Taylor hydrodynamic instability to achieve thermoregulatory homeostasis in confined fluidic devices, where the calibration of rheology, chemistry, and geometry gives rise to versatile thermo-responsive behaviors that parallel those observed in nature.

First, I will introduce our ‘HISTEMI’ platform (Homeostatic Interface for Solar and Thermal Environmental Management using Instability), termed after the Greek root for homeostasis. I will largely focus on the unique energy management behaviors enabled by the non-linear temperature-dependence of the hydrodynamic instability on which HISTEMI relies. Next, I will discuss the implications of HISTEMI for accessing what we call ‘customizable homeostasis’ – a new temperature management paradigm that fuses the benefits of typical passive systems (autonomy) with those of typical active systems (tunability). A suite of optical and thermodynamic energy-balance models reveals the potential energy savings of this hybrid thermoregulatory modality. Finally, I will make the case for ‘engineered-instability’ as a paradigm to access new functions that unconventionally address challenges in energy management, human comfort, and sustainability.