The effective wake distribution is an important factor in propeller design. Today it is impossible to carry out a numerical calculation of this distribution for real ship hulls. The extrapolation of a model measured wake to full scale seems to be more successful. At this extrapolation the influence of viscosity must be considered because the Reynold's numbers for a model and ship differ by powers of ten. Besides that the influence of the working propeller has. to be hated, when starting from the nominal wake. Thus it is useful. For the extrapolation to start from the wake at the working propeller. The wake distribution – on different propeller loadings – was measured with the Laser-Doppler Anemometer (LDA). To get the effective velocity field, the propeller induced velocities were calculated by means of the expanded lifting line theory. These velocities Were subtracted from the measured ones. This wake distribution was compared with the nominal one.

Keywords:
propeller, calculation, determination, procedure, frequency, extrapolation, ship, din front, naval architect, world trade center suite 1369
This content is only available via PDF.
Copyright 1981, The Society of Naval Architects and Marine Engineers
You can access this article if you purchase or spend a download.