Time-Accurate Analysis of the Viscous Flow Around Puller Podded Drive Using Sliding Mesh Method

In this paper a computational method is presented for predicting the unsteady hydrodynamic forces acting on podded drive components. These numerical simulations are performed with the aim of accurately studying the interaction between the propeller, the pod, and the strut. In order to simulate the unsteady viscous flow around a puller type podded drive, a Reynolds-Averaged Navier–Stokes (RANS) solver is used. The time-accurate calculations are made by applying the sliding mesh method. Structured and unstructured mesh techniques are used for the propeller and podded drive. The method is applied in the case of the straight condition. The unsteady propeller thrust and torque coefficient fluctuations are predicted for advance velocity ratios ranging from 0.2 to 1.0. The time averaged forces of the podded drive obtained by an unsteady analysis are compared to and verified by the steady result and the experimental data. Finally, discrepancies between the simulation results and the experimental data have been quantitatively evaluated in terms of the relative percentage error for the propulsive characteristics.