Research on the cavitation characteristics in viscous oil around parameterized hydrofoils

Fluid machinery using viscous oil as the working medium is a critical factor in determining the efficiency of the entire system. The oil operates at high speeds and over a wide range of temperatures, making it prone to cavitation. Therefore, studying cavitation phenomena in viscous oil is of significant importance. By analyzing cavitation states under different flow conditions and hydrofoil structures, it was found that the cavitation number at inception ranges from 2.28 to 1.89. Furthermore, the cavitation number for the transition from attached cavitation to periodic cavitation ranges from 1.58 to 1.35. Moreover, an increase in the camber of the hydrofoil intensifies the unsteady characteristics of the flow field. However, as the cavitation number decreases, the influence of periodicity on the camber gradually diminishes. Additionally, three distinct types of cavitation regions were identified on the hydrofoil surface: the cavitation inception region, the wall separation region, and the cavitation reattachment region. When the camber of the hydrofoil was increased from 1% to 6%, the cavitation inception position and the length of the reattachment region changed by 32.2% and 87.9%, respectively.