<p>Centrifugal pumps in the ballast system of icebreakers play a critical role in ensuring the normal navigation and reliability of ships. In polar environments, ballast water pumps may inadvertently ingest ice–water mixture, which can compromise their operational stability. In this study, the impact of ice particle ingestion on the flow characteristics within a pump was examined using numerical simulation methods. By employing computational fluid dynamics and the Mixture multiphase flow model, the turbulent kinetic energy distribution, entropy generation, and their interaction with cavitation phenomenon under different ice particle conditions were systematically studied in this paper. The findings revealed that entropy generation within the pump primarily originated from turbulent dissipation and wall friction. As the size and concentration of ice particles increase, both entropy generation and turbulent intensity exhibited an upward trend. Furthermore, the Pearson correlation coefficient between the cavitation and entropy production distribution data in the blade region is approximately − 0.75, which suggests a moderate negative relationship between these two variables. Especially at the boundary of the cavitation region, the entropy generation tended to be significantly higher. This research can provide a theoretical foundation for the hydraulic optimization design of ballast systems in polar-specialized vessels when handling dense ice–water mixtures.</p>