Cylinder wake effect on cavitation flow field around a downstream hydrofoil

In this study, the effect of the upstream cylinder wake on the cavitation flow field around a downstream hydrofoil is investigated using the implicit large eddy simulation (ILES) method in combination with the Schnerr-Sauer cavitation model. By varying the cavitation number (σ) and the hydrofoil angle of attack (α), the evolution characteristics of wake vortices, the pressure fluctuation spectrum (CP′), and the variation in cavitation volume fraction are examined. The results indicate that the vortex shedding frequency of the upstream cylinder plays a dominant role in governing the flow field instability and cavitation behavior of the downstream hydrofoil. Under low σ conditions, the small-scale vortex structures within the wake cavity significantly suppress the propagation of CP′. As σ increases, the wake cavity shrinks, and the vortices evolve into large-scale vortex streets, with vortex shedding frequency becoming the primary driver of CP′ fluctuations on the hydrofoil. Furthermore, variations in the hydrofoil's angle of attack alter the interaction location between the wake vortices and the hydrofoil surface, influencing the periodic fluctuations of the cavitation flow field.