Large Eddy Simulation of a Cavitating Propeller Operating in Behind Conditions with and without Pre-Swirl Stators

Paper i proceeding, 2015

The hull-propeller interaction of a single-screw transport ship is investigated in model scale using large-eddy simulation in both a baseline configuration and one with a pre-swirl- stator installation. Simulations are performed for both non- cavitating and cavitating conditions. The analysis is focused on the unsteady effective wake, its impact on the propeller, and how this is affected by the installation of the stator blades upstream the propeller. A complete geometrical model of the propeller is included in the simulations using sliding interfaces. Computed quantities include the time-resolved thrust, torque and side forces on the propeller, as well as the load on individual blades. The sim- ulated unsteady flow field in the stern region and around the propeller blades is studied in detail for the wetted conditions. Results are also provided for the cavity extent in both con- figurations. Limited comparison with experimental measure- ments is carried out both for the flow field and forces on the propeller. A discussion is included concerning some differ- ences noted between the baseline and the stator configuration and how that potentially impacts propeller design considera- tions and system performance.