An Experimental Study of the Wake Behind a Ten-Bladed Propeller With and Without Ingested Turbulence

The focus of the present research was the evolution of the wake downstream of a ten bladed propeller. Previous experimental efforts have examined the wake at a single downstream location with upstream turbulence. The present experiments focused on the development of the wake by traversing an X-wire probe across the radius of the propeller at six axial locations. The data were acquired at two advance ratios, and two inflow turbulence levels. The blade position was monitored so that relevant statistics could be calculated in the rotating reference frame. Plots of the mean and RMS velocities for each of the three directional components at all downstream locations have been created for comparison with computational results. Two different methods were used to separate the blade wakes from turbulent fluctuations. A wake half width was calculated from the mean streamwise velocity component and the Karhunen-Lo$grave{e}$ve decomposition was used to separate blade wakes and turbulent velocity fluctuations with promising results. The current investigation will provide data and confirmation of experimental techniques and theoretical predictions to be implemented on full size surface ships and submarines.