Figure 2: Schematic overview of PIV setup at starboard


visible in the measurements. However, the CFD results show a smooth axial velocity contour because the bracket was not modelled. The effects of both shaft rotation and V-bracket wake in the propeller wake field are small and will not influence an actual propeller design. However, for other ships, hence other geometries, such effects can increase sig- nificantly and this necessitates modelling of these details in the CFD calculations. Comparisons of results along the rest of the shaft line provides more insight and it


is possible in regions where no comparison was done before.


The quality and complexity of CFD is in- creasing rapidly and we are getting very close to a full-appended hull. However, there is always a trade-off. MARIN is constantly assessing the correct level of detail neces- sary to provide high quality results. It is now even more important to compare CFD with measurements and PIV can provide the necessary high quality data. Finally, this brings a full understanding of the 3D flow field within reach.


Figure 3: Comparison of CFD and PIV results for the axial velocity in the propeller plane; left: without shaft rotation in model test, right; with shaft rotation. Colours represent results from PIV, black lines from CFD.


1991


First software delivered for PC/DOS


1992


Foundation Maritime Simulation Centre Netherlands (MSCN)


1993


First MARIN Hydrodynamic Courses


report 11


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