Numerical Study of Cavitating Flows in an External Gear Pump with Special Emphasis on Thermodynamic Effects

Cavitation is a critical phenomenon in hydraulic systems, particularly in gear pumps, where it can significantly affect performance and reliability. This study uses numerical simulations with the Full Cavitation Model and k-ε turbulence model to investigate the thermodynamic effects of cavitation in gear pump lubricating oil at varying temperatures. It focuses on the formation and evolution of cavitation vortex structures in the outlet bridge area. The simulations reveal significant heat exchange between liquid and vapor phases, causing a local temperature drop and a reduction in saturated vapor pressure, which suppresses cavitation development. As temperature increases, this effect diminishes due to the lower density of the hydraulic oil.