Applications of direct numerical simulations to interfacial problems

The fluid mechanics associated with the interface between two fluids, and in particular air and water, is of obvious importance in applications such as remote sensing, and the characterization of the environment. In remote sensing applications interfacial dynamics play a role in determining signatures in the radar, infrared, and visible wavelengths of the electromagnetic spectrum. These dynamics also play an important role in the determination of the interfacial flux of heat, mass, and momentum at the air-sea interface. In particular, accurate estimation of carbon dioxide flux and aerosol production has a direct bearing on our ability to predict climate change. Here we will discuss the current progress that has been made in applying direct numerical simulations (DNS) to some of these problems. We will illustrate the use of DNS to study the relatively simple case of a flat interface subject to shear and an outgoing heat flux.