Numerical Investigation of the Impact of Sea Spray Droplets on Air-Sea Boundary Layer

Sea spray droplets can have a significant impact on the mass, momentum, and heat transfer between the atmosphere and oceans. In this study, we use numerical simulations to investigate the air-spray-ocean interaction process. In the computational framework recently developed in our group, we incorporate a Lagrangian droplet tracking technique to the direct numerical simulation (DNS) and large-eddy simulation (LES) of the turbulence wind field to study the motions of sea spray droplets in the air-sea boundary layer. We also include the thermal and evaporation responses of droplets to study the feedback mechanism of sea spray droplets on air-sea enthalpy transfer. The initial numbers of sea spray droplets with different diameters are determined by the sea spray concentration function. From the simulations, we obtain the distribution of sea spray droplets and investigate their effect on sea surface drag under different wind speed and wave age conditions. The results indicate that sea spray droplets contribute to a considerable amount of air-sea heat flux in high winds.