Rouhollah Fatehi

Kelvin-Helmholtz instabilities (KHI) a fluid dynamics phenomenon, occurs when there is velocity shear in a single continuous fluid, or where there is a velocity difference across the interface between two fluids. It can emerge in tidal flows interacting with movable sandy beds, influencing sediment transport. This paper investigates the emergence of KHI in the Persian Gulf near the Bushehr port using satellite imagery and numerical simulations. Images show repetitive billow patterns forming under certain tidal currents, with variations depending on flow speed and sediment concentration. Simulations using a 2D Smoothed Particle Hydrodynamics model demonstrate the growth of small interfacial waves into larger billows over time. Results show the effect of the Richardson number, with increased gravitational forces at higher Ri yielding smaller vortices. Overall, findings provide new insights on conditions triggering KHI in tidal environments and subsequent effects on sediment movement. Further field measurements and 3D modeling can enable more robust quantitative comparisons.