This study examines the performance variations and flow field characteristics of a submerged water-jet propulsor under complex oblique sailing conditions, providing theoretical insights for propulsor design optimization and ship maneuverability improvement. Both steady and unsteady numerical simulations were performed, with the unsteady analysis employing an actuator disk model. The results indicate that at a positive drift angle of 30°, the propulsor head decreases by approximately 6%, whereas at a negative drift angle of 30°, it drops significantly by 28%. The entropy generation distribution among the propulsor components was analyzed based on entropy generation theory, revealing that turbulent dissipation contributes the largest portion (64%) of the total entropy generation, with the impeller flow passage accounting for 47%. Furthermore, pressure fluctuations on the propulsor housing surface were evaluated under unsteady conditions. The findings show that a twin-jet configuration with an optimal spacing of 1.6D effectively minimizes flow field interference during maneuvering. Overall, the study provides a theoretical foundation for enhancing the design and hydrodynamic performance of submerged water-jet propulsion systems.
Yang et al. (Fri,) studied this question.