As part of a collaborative research programme, MARIN has carried out model tests to compare the performance of the ABB Dynafin propulsion concept with a conventional propulsion configuration on a RoRo vessel. The model tests confirm that ABB Dynafin can deliver a 22 per cent energy saving.
The trials were conducted in cooperation with ABB and shipowner LD Armateurs (LDA). Using identical RoRo hull forms, self‑propulsion model tests were performed to enable a direct and objective comparison between ABB Dynafin and a conventional twin‑shaftline arrangement.
The validation programme combined advanced computational fluid dynamics (CFD) calculations with dedicated model tests, measurement systems and transducers to determine hydrodynamic loads and propulsive efficiency. The outcomes are consistent with results obtained in earlier MARIN studies on ABB Dynafin and confirm the suitability of the applied test methodology for evaluating innovative propulsion concepts under controlled and reproducible conditions.
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ABB Dynafin
Mimicking the movement of a whale’s tail, ABB Dynafin is a cycloidal propulsion system comprising a horizontal wheel rotating at thirty to eighty revolutions per minute (RPM) and vertically descending blades. The pitch and angle of the blades are individually controlled in real time, delivering optimal hydrodynamic efficiency and instant thrust vectoring while reducing noise and turbulence.
‘ABB acknowledges that implementing ABB Dynafin propulsion for newbuild vessels requires further validation by independent third parties, and close collaboration with shipowners,’ says Janne Pohjalainen, Global Product Line Manager, ABB Dynafin. ‘Before this type of testing could take place at MARIN’s model basin, we needed to design and build the model-scale propulsion units, including all the control technologies and user interfaces.’
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Test results
Two ABB Dynafin systems equipped with MARIN transducers were fitted at the stern of a ro-ro vessel model for the tests. ‘The thrust and torque on the main wheel, including the side force, as well as the torque on each fin, were measured, says Dr. Jie Dang, Senior Project Manager, MARIN. ‘Both the hull efficiency and the relative rotative efficiency were recorded as “larger than one”, meaning favourable interactions between the propulsors and the hull.’
At the vessel’s design speed of 17 knots in ideal trial conditions, the ABB Dynafin units required approximately 22 per cent less delivered power than the twin-shaftline setup.
Dang also sees untapped potential to exploit the unit’s thrust vectoring capability for use with wind-assisted ships by incorporating AI-driven, self-learning controls to boost real-time fuel optimisation, while also achieving roll damping and heeling correction and supporting better energy regeneration.
Picture: The ABB Dynafin propulsion system on the RoRo model used by MARIN (image from the ABB video above).
Also read: VIDEO: MARIN verifies efficiency of ABB Dynafin propulsion
