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Putting a new spin on propeller design


With regard to propeller design MARIN focuses on the best possible compromise between the propulsive efficiency and cavitation nuisance, and how further improvements can be made. Evert-Jan Foeth, John Huisman & Arjan Lampe, j.huisman@marin.nl


research and cruise ships with delayed cavitation inception, high performance propellers for merchant ships, or propellers for special purpose vessels such as dredgers, tugs and fishing vessels.


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Currently, we are redesigning our propeller design process. For example, we used to set the diameter applying best-practice guidelines for propeller-hull clearance. Now we specify the maximum force allowed on the hull and ask ourselves: what is the best propeller design within those limits? By setting important propeller parameters at the end of the design process, and not at the beginning, we can obtain a better design. The latest design techniques are used, such as multi-objective optimisation techniques that can: • Thoroughly explore the many design opportunities within the design space


• Analyse the propeller in all the relevant conditions simultaneously


• Visualise trade-offs between conflicting objectives


Figure 1: Example of an optimisation case with the Pareto front in red. The margin against cavitation inception and efficiency are maximised. CPN is the pressure coefficient and σ И the cavitation number.


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• Quantify the influence of design choices, constraints and limitations on the objectives


his applies to a wide range of designs such as high-end, ‘low- noise’ propellers for yachts, naval,


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