摘要

An electric rim driven thruster is a relatively new marine propulsion device and the associated fluid dynamics have not been fully investigated. This work develops a robust CFD method and investigates both frozen rotor and unsteady simulations of rotor-stator interaction. Two solvers from OpenFOAM were used. Steady state simulations were performed using MRFSimpleFoam with a frozen rotor treatment of the interface between static and rotational reference frames. The solver for unsteady simulations was pimpleDyMFoam, utilising a sliding mesh interface to handle the dynamic meshing. Both methods are thoroughly verified and validated against experimental data. The k-omega SST turbulence model is found to be robust down to low advance ratios. For the rim driven thruster, analytical models are used to estimate friction forces in the rim gap and their contribution to torque losses. The frozen rotor and unsteady treatments of rotor-stator interaction are compared and found to have similar trends in the variation of thrust produced. However, the frozen rotor method does not predict the same variation of instantaneous torque and does not capture the rotor-stator interaction fully. Analysis of the unsteady rotor-stator interaction shows an oscillating flow over the stators and thus inflow to the blades.

  • 出版日期2015-9-15