Abstract

The ability to predict the behaviour of multiphase flows accurately, reliably, and efficiently addresses an absolutely vast array of major challenges of societal, economic and scientific importance. Flows with multiple interacting fluid phases give rise to phenomena at liquid-gas interfaces whose deep and quantitative understanding is crucial for solving global challenges such as ocean-atmosphere greenhouse gas exchange, capture or storage of CO2 , aerosol and cloud physics and water desalination and treatment. Such real and varied systems are necessarily quite complex, often turbulent, multiphase flows where mass (chemical species), momentum and energy (heat) are exchanged across, usually contaminated, surfactant-laden interfaces between phases which may themselves exhibit non-Newtonian rheology or even change phase. In health, energy and engineering applications, such flows are central to nearly every processing and manufacturing technology such as microfluidics lab-on-a-chip for biomedicine, mixing, scrubbing, refining and distillation in chemical processes, atomisation, jets and sprays in combustion, surfactant enhanced flows in oil-water petroleum processes and detergents, bubble formation in glass, ceramics or steel production, alloy solidification in materials processing and boiling of water to steam for fossil fuel and nuclear energy production just to name a few. In addition, one of the most crucial aspects of these systems is the two-way coupled interaction of fluid flows with intricately designed solid structures such as impeller mixers, atomisation nozzles or distillation packings upon which dynamic fluid contact lines evolve.

In real systems, the above complexities are the rule not the exception and the crucial commonality is the interface, whether it be between liquid, gas or solid. I will present an overview and some examples of our work towards simulating some of these interfacial flows to a high degree of precision in order to try to bring them into the domain of what is computationally achievable.