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CFD Simulation for Propeller Four-Quadrant Flows

A Reynolds-Averaged Navier-Stokes (RANS) method has been employed in conjunction with an overlapping moving grid approach to provide accurate resolution of four-quadrant propeller flows under both the design and off-design conditions. It is well known that some off-design propeller flow phenomena are dominated by viscous effects and cannot be accurately predicted by the potential flow methods. In order to properly account for viscous effects, it is necessary to employ accurate and robust numerical methods which can provide detailed resolution of the propeller boundary layer, turbulent wake, leading-edge separation, and unsteady ring vortices induced by propeller operations under off-design conditions. In this study, time-domain simulations are performed for the DTRC 4I18 propeller under ahead, bollard pull, crash-ahead, crash-astern, and backing conditions and compared with the available experimental data.