Transforming Fluid Instabilities into Smart Materials—Non-Equilibrium Pattern Dynamics for Thermoregulatory Homeostasis

Emerging pattern dynamics in natural systems have fascinated materials scientists for decades. Ordered patterns can evolve within non-equilibrium systems when driven to instability, where emergent instability-mediated phenomena underly the morphology of snowflake crystals, bacterial colonies, microorganisms, and retinal vessels.<br/><br/>In this talk, I will discuss our recent efforts to harness pattern dynamics and instability to develop smart, bio-inspired, self-regulating materials, toward addressing 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 rationally-engineered devices, where the calibration of rheology, chemistry, and geometry gives rise to intelligent and versatile thermo-responsive behaviors that parallel those observed in nature.<br/><br/>First, I will introduce a platform we call HISTEMI (Homeostatic Interface for Solar and Thermal Environmental Management using Instability), after the Greek root for homeostasis; I will then demonstrate some of the unique environmental management behaviors enabled by the non-linear temperature-dependence of the underlying hydrodynamic instability.<br/><br/>Next, I will discuss the implications of this class of smart materials for accessing what we call ‘customizable homeostasis’ – a new temperature management paradigm that fuses the benefits of typical passive systems (low-energy feedback) with those of typical active systems (high-precision control). Results from a set of optical and thermodynamic energy-balance models will reveal the potential energy savings of this thermoregulatory modality across global sectors, from transportation to agriculture, residential housing, and power generation.<br/><br/>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.