Three-dimensional steady and unsteady Euler equation solvers are developed to model the flow field around a marine propeller subject to a non-axisymmetric inflow, and to obtain the corresponding steady and unsteady effective wake. The finite volume method (FVM) is applied to solve the incompressible Euler equations over a domain which can be bounded by the hub and tunnel walls. The unsteady influence of the propeller is modeled in the Euler equations via the body force terms which vary according to the blade loading. The Euler solver is coupled, through an iterative process, with an existing unsteady cavitating propeller potential flow solver which is based on the vortex lattice method (VLM). The coupling is achieved in the following two ways; (a) the pressure distribution computed in the VLM is converted into body forces distributed over the cells which are intersected by the blade surface in the FVM, and (b) the total velocity in front of the propeller computed in the FVM is converted into the effective wake velocity which is used as inflow in the VLM.; The finite volume method is first applied in the case of the steady two-dimensional flow around a hydrofoil. It is shown that the two-dimensional flow field can be reproduced, within acceptable accuracy, using the finite volume method and by replacing the hydrofoil with an appropriate distribution of body forces. Then, several validation tests of the steady and unsteady Euler solvers are performed using a variety of propeller geometries and conditions, including the cases of actuator disk, uniform inflow, and propeller inside a tunnel. The predicted velocity field upstream of the propeller and the unsteady cavity shapes show very good agreement with those measured in previously performed experiments. For a given non-axisymmetric nominal wake inflow, the fully unsteady effective wake can be computed using the unsteady Euler solver. However, for the tested cases the unsteadiness of the computed unsteady effective wake has been found to be small. For these cases, the time average of the unsteady effective wake, predicted using the unsteady Euler solver, has been found to be very close to the steady effective wake predicted using the steady Euler solver.
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