Prediction of the Cavitation Effect on the Flow Around the Outboard Motor Propeller Blade Hydrofoil Section Using CFD

The propeller blade hydrofoil section is one of the factors that determines the propeller performance. In the development of the hydrofoil, repeatedly performed experiments using many foil models and the cavitation tunnel involve extended time and high cost. This is why there are expectations for the numerical simulation to realize shorter development time and cost cutback. On the other hand, a technique for reproducing the hydrofoil characteristics taking account of the cavitation effect using CFD (Computational Fluid Dynamics) has hardly been established. There is no example of performance prediction especially for a hydrofoil section of the outboard motor propellers in which the trailing edge is cut off.

This paper describes the results of the prediction of hydrodynamic characteristics performed in regard to the two differently shaped outboard motor propeller blade hydrofoil sections taking account of the cavitation effect. Calculation was performed by commercial finite volume method CFD code. One-fluid type cavitation model was employed, which is calculated simultaneously with RANS (Reynolds-Averaged Navier-Stokes) equations. The numerical calculation results were compared with experimental data taken in the cavitation tunnel to show their effectiveness and the limit of application.