Research topic:

Optimal Design of Marine Propellers

Aymen MEFTI, 2025

The oceans cover approximately 71% of the Earth's surface, making maritime navigation an essential component of global transportation and trade. Many countries rely heavily on marine cargo transport to sustain their economies and supply their populations. At the core of most marine propulsion systems, the propeller plays a critical role in converting the mechanical power generated by the engine into effective thrust to overcome hydrodynamic resistance. Despite significant advancements in propeller design, several challenges persist, particularly those related to cavitation – which leads to performance degradation, noise emission, and material erosion – and hydroacoustic issues that can affect passenger comfort and marine life. Furthermore, rising fuel costs reinforce the need for propellers that achieve higher efficiency while reducing cavitation inception and hydroacoustic emissions.

The optimal design of marine propellers is therefore a complex multi-objective optimization problem. Traditional experimental methods, although valuable for reproducing real physical phenomena, remain limited due to their high cost and the complexity of the underlying physics. This has led to an increased reliance on numerical simulation techniques, which offer greater flexibility in exploring design variations. However, numerical methods must balance simulation fidelity with computational cost. Integrating numerical tools into the optimization process thus requires a strategy that enables both broad exploration of the design space and targeted refinement of promising solutions.

A multi-fidelity approach addresses this need by combining low-fidelity methods – such as Blade Element Momentum Theory (BEMT), which enables rapid evaluation of large design spaces – with high-fidelity techniques such as Computational Fluid Dynamics (CFD), used to refine and validate optimal designs. This hierarchical integration supports efficient and accurate development of high-performance marine propellers.


Aymen MEFTI is visiting scholar at Aircraft Design and Systems Group (AERO) from École Militaire Polytechnique (EMP). Registered at Center for Postgraduate Studies (CPS), Hamburg University of Applied Sciences (HAW Hamburg).