Germans researchers are commencing a novel scientific endeavor focused on tackling one of the most pressing ecological challenges facing the World Ocean. Ship propellers generate significant sound waves that gravely impact aquatic life. This acoustic pollution disrupts the established patterns of communication, foraging, and reproduction among marine animals. A team of specialists from the HAW Kiel company is currently developing improved propeller designs capable of substantially mitigating underwater noise levels.
The government of the state of Schleswig-Holstein is backing these efforts, supplying funding via a grant amounting to 390,000 euros. The initiative, officially named MinKav, began on January 1st, 2026. The research objective is to decrease underwater acoustic pollution without compromising vessel speed or performance. Achieving this balance is vitally important for the future of global maritime transport.
Acoustic noise emanating from propellers is caused by a physical phenomenon known as cavitation. On the suction side of the rotating blade, pressure drops sharply, resulting in water vaporization and the formation of minute gas pockets. When the pressure normalizes, these bubbles violently collapse, creating loud impulsive sounds that travel considerable distances.
The research is being overseen by Leonie Föring at the Institute of Ship Technology and Transport Systems. To meticulously study these bubble structures, she is utilizing a specialized cavitation hydrodynamic tunnel, high-speed cameras, and extremely sensitive underwater microphones. Her primary goal is to visualize processes that are normally unseen and record sounds that are typically inaudible. Föring explains, “A powerful sound impulse is created at the instant a bubble implodes. Our immediate task is to ascertain if it is fundamentally possible to delay this moment and what alterations to propeller geometry are necessary to achieve this.”
Although contemporary commercial vessels already feature modified propeller shapes, noise reduction underwater was seldom a primary concern for design engineers in the past. Professor Jörn Kröger, who leads the project, firmly believes this situation must undergo a radical shift. Existing methods frequently necessitate ships reducing their speed, inevitably leading to extended transit times and increased operational expenses. Föring and Kröger are employing computational fluid dynamics (CFD) simulations to discover a more effective method for protecting marine inhabitants while preserving energy output.
The company JASCO-ShipConsult, possessing deep knowledge in naval acoustics, is participating in the project. Dr. Dietrich Wittekind, a shipbuilding expert, notes that the global scientific community has been investigating low-frequency noise for two decades, yet a complete, fundamental understanding of the mechanism remains elusive. The MinKav scientific work is scheduled through December 31st, 2028, and holds the potential to become the first effort to introduce concrete, readily applicable noise reduction techniques.
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