Crescent pumps are a particular type of internal gear pumps and are extensively employed in fluid power applications because of their compact architecture and capability to work efficiently at elevated pressures and rotational speeds. Owing to these features, they are particularly well suited for automotive systems, especially for engine lubrication applications. However, accurately predicting the performance of these pumps is still a complex task, since their behaviour is strongly influenced by the interaction between geometric characteristics, fluid properties, and operating conditions. In particular, key performance indicators such as flow rate, volumetric efficiency, and flow ripple are strongly influenced by internal leakage and the detailed geometry of the pump components.