COMPIT 2010 in Gubbio - TUHH

6. Conclusion
In comparison to a conventional propeller the design of a multi-component-propulsor is more
sophisticated. The application of modern optimisation methods is necessary to achieve a design,
which is able to fulfil the most important design requirements.
The drawback of applying optimisation methods is the over-proportional increase of computation
effort. Due to the high number of design variables of a multi-component-propulsor, a huge quantity of
designs has to be created in order to estimate the influence of design parameters on the performance
of the developed geometries. Therefore it is important to combine the advantages of calculation
methods for potential and for viscous flow to reduce the computation time and accelerate the
optimisation.
From the hydrodynamic point of view multi-component propulsors are more efficient than propellers
at a certain ship speed range and for certain applications. The employing of the duct can be helpful
also for ships working in extremely shallow water because the duct protects the propeller in grounding
case. Another important advantage of the employing of the duct is the expected reduction of the
hydro-acoustic impact on the environment. The expected high manufacturing costs make multicomponent
propulsors for conventional commercial applications too expensive.
References
HUNDEMER, J.; NAUJOKS, B.; HACHMANN, T.; ABDEL-MAKSOUD, M. (2006), Design of
ship propellers with evolution algorithms, Jahrbuch der STG, Springer
JÜRGENS, D.; HEINKE, H.J. (2006), Investigation of deeply submerged waterjet, Jahrbuch der STG,
Springer
KERWIN, J.E. (2006), Hydrodynamic issues in waterjet design and analysis, 26 th
Hydrodynamics, Rome
Symp. Naval
KIM, K.H. (2006), Waterjet propulsion for high-speed naval ships, Advanced Naval Propulsion
Symp., Arlington
STEDEN, M.; HUNDEMER, J.; ABDEL-MAKSOUD, M. (2009), Optimisation of a linearjet, 1 st Int.
Symp. Marine Propulsors, Trondheim
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