Abstract: This paper presents a detailed numerical study of cavitating flow over a NACA66 hydrofoil at a cavitation number of 0.99. Validation against experimental data demonstrated accurate prediction of cavity dynamics, lift and drag forces, and shedding frequency. The effects of surface roughness were analyzed, showing performance degradation with increased roughness, where a smooth surface yielded the best hydrodynamic efficiency and stable cavitation behavior. The study underscores the potential of the surface texture as a passive control method to mitigate cavitation-induced instabilities while preserving hydrofoil performance, providing valuable insights for the design of efficient cavitating hydrofoils and propulsors.

Key words: CFD, FLUENT, cavitation, roughness, control.