MARIN has a long history in research into the performance of thrusters during Dynamic Positioning (DP) operations. Research on ducted propellers started in the late 1960s (Oosterveld) but a lot of today’s knowledge on thruster interaction effects was developed in the late 1980s and early 1990s (Nienhuis).


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probe thruster interaction effects


Hans Cozijn j.l.cozijn@marin.nl 10 report initiatives New


s a result of the application of DP systems on many different vessels, there is continued interest in this


subject. Today, newly developed tools enable more detailed measurements and computer simulations of the thrusters on DP vessels. This has lead to new research initiatives to improve the understanding of thruster interaction effects.


During DP operations the effective force generated by thrusters can be significantly smaller than would be expected based on the thrusters’ open water characteristics. This is a result of thruster interaction with the hull, current and the wake of neigh- bouring thrusters. The understanding and quantification of thruster interaction (or thrust degradation) effects is essential for an accurate evaluation of the station-keeping capabilities of DP vessels.


At present, thrust degradation effects can be quantified using data available from literature, or by carrying out dedicated model tests. Published data can give valuable insights but often it is too general, or not applicable to the specific design. Model tests, on the other hand, do provide detailed results but they are relatively expensive. In addition, model test results


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