Turbulent channel flow with liquid infused walls

Liquid-Infused Surfaces (LISs), consisting of textured substrates impregnated with lubricants, are a promising class of engineered surfaces capable of serving as anti-icing devices for aircraft or reducing the skin-friction drag of marine vehicles thanks to their intrinsic slippery behaviour. In this work, we have performed direct numerical simulations of a turbulent flow over an LIS with longitudinal grooves, by considering the influence of different physical and geometrical parameters such as the Weber number and the fluid-area fraction. The coupled dynamics of the bulk flow and the infused lubricant is modelled using a phase-field approach. The turbulence modifications and the friction properties of the texture are discussed in terms of surface tension and effective slip length. The simulations highlight the role of the interface in the suppression of wall-normal velocity fluctuations, which, together with wall slip, represents a key ingredient for effective drag reduction.