Wake Field



For a good propeller design it is necessary to have detailed knowledge of the nominal wake field and also the velocity distribution in the propeller plane. For experimental determination of wake fields, 5-hole ball probes, LDA or PIV (“Particle Image Velocimetry”), are used. It is standard that a 5-hole ball probe is used, offering the following options:

  • Measurements in the propeller plane
  • Measurements at the point of appendages, ie. the shaft struts
  • With the probe, any coordinates can be approached
  • 3-Dimensional wake field measurement

The standard measurement of a wake field for single screw vessels is carried out on 6 radii respectively, every 5 °. For measurements behind podded drives and shaft struts among others, the resolution is adjusted accordingly.

In addition to the experimental determination of the wake field, a calculation based on CFD simulation is possible. An advantage of a CFD simulation is the calculation of the velocity field for the Reynolds number of the full-size version.


Context Related References / Research Projects

[1] Anschau, P., Mach, K.-P.: Application of a Stereo PIV System for Investigations of Flow Fields in Towing Tank and Cavitation Tunnel, HYDRONAV 2007, Wroclaw, Polen, September 2007
[2] Grabert, R.: Der Einfluss unterschiedlichster Betriebszustände eines Schiffes auf das Nachstromfeld, 3. SVA-Forschungsforum, Potsdam, 28. Januar 2010:
[3] Lübke, L.: Formoptimierung unter Berücksichtigung der Charakteristik des Nachstromfeldes, 4. SVA-Forschungsforum, Potsdam, 27. Januar 2011