Experimental optimisation of the man overboard manoeuvre Bas J. de Kruif, Bülent Düz, Victor Ferrari Applied Ocean Research, 2025 In maritime operations, the safety of crew and passengers is paramount, making the man overboard manoeuvre a critical emergency procedure for all vessels. Among the different ways to perform this manoeuvre, the Williamson turn is used to come back on its own wake to retrieve the man overboard. This manoeuvre is especially useful if it is not precisely known when the person fell overboard. During this manoeuvre the rudder is switched to its extremes at well defined heading deviations. The IAMSAR guideline provides standard values for these, but these values do not guarantee that the vessel will sail back on its own wake. In this study we first estimated these switching angles with a numerical model and a data-driven model. Next, we used update rules to fine-tune these switching angles and tested those in a 1:24 model-scale experiment in one of MARIN’s basins. After one iteration in the basin the lateral error and heading error were within DNV GL’s guidelines. The predicted switching angles from the numerical model were closer to the experimentally found values. However, the course and speed were better predicted with the data-driven model. The approach lends itself well to minimise commissioning time of a new vessel, and the switching angles found could be included on the wheelhouse-chart for a better execution of the Williamson turn. • An iterative procedure is developed for optimising a man overboard manoeuvre. • The method determines heading angles for rudder switching. • The procedure was tested in simulations and validated in model-scale experiments. • The vessel returned to the start position within 20m, and 2° course deviation. • A detailed numerical model and a data-driven model provided initial angles.
Ship trajectory prediction using encoder–decoder-based deep learning models Bülent Düz, Erwin van Iperen Journal of Location Based Services, 2025 Accurate prediction of ship trajectories can be an important capability for various maritime transport applications, such as vessel traffic services (VTS), traffic flow assessment, and collision avoidance systems. The widespread availability of AIS (Automatic Identification System) data and the progress made in the deep learning methods in the last decade motivate us to attack this problem from a data-driven perspective. This paper presents the results of a study where various encoder–decoder architectures were applied to the ship trajectory prediction problem using AIS data that were collected from the Rotterdam port approach area. The models were trained with the AIS data along four routes belonging to different ship types/lengths without any clustering or filtering. An average position RMSE of 1.6 km was obtained when the best-performing model predicts ship positions 30 min into the future using 60 min of historical data.
QUANTIFYING UNCERTAINTIES IN NUMERICAL PREDICTIONS OF DYNAMIC CAVITATION Uncecomp Proceedings, 2023
MITIGATING SPURIOUS LOW-FREQUENCY WAVES IN A MODEL BASIN WITH A RAMPED FLOOR Bülent Düz, Jule Scharnke, Jaap de Wilde Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering OMAE, 2022 Low-frequency (LF) content of the waves present in a finite model basin may have multiple sources and associated consequences. Typically the horizontal natural periods of the moored structures are long and in the same range as the LF range. As such, the response of the moored structures in shallow water might be significantly affected by the spurious LF waves. The first goal here was to investigate whether the available numerical simulation tools can capture the underlying physics regarding the spurious LF waves in a basin with a ramped floor. It was seen that even though the heights of the short waves were underestimated when reflected waves from the beach reached the area of interest, the heights and phases of the LF waves were captured with an acceptable accuracy. The second goal was to investigate the approach of generating a correction signal (otherwise known as “anti-wave”) in order to mitigate the spurious LF wave content in the basin. The results of the CFD simulations showed that it was possible to reduce the amount of spurious LF waves. Following this outcome, the approach was tested in a model basin at MARIN with a ramped floor (the Offshore Basin - OB). The experiments were carried out with and without an LNG tanker in the OB using an irregular wave at one water depth. The measurements showed that the spurious LF content was mitigated with the correction signal. As a result, a reasonable reduction in the low-frequency surge motion of the ship was observed.
CONSISTENCY ASSESSMENT OF WAVE DIRECTIONAL SPECTRUM PREDICTIONS FROM MACHINE LEARNING BASED SHIP-AS-A-WAVE-BUOY METHODS T. P. Scholcz, B. Düz, R. B. Hageman, B. Mak Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering OMAE, 2022 Real-time knowledge of the ocean wave directional spectrum is valuable for maritime safety and navigation. When end-to-end machine learning is used to learn ocean wave directional spectra from ship motions, the spectrum predictions may be inconsistent with measured ship motions from a physical point of view. In order to assess this consistency, a method is proposed that makes use of a numerical seakeeping code to recalculate ship motions from predicted wave spectra. The recalculated ship motions are subsequently compared to the measured ship motions. The method is applied using data from three different vessels, each having a different level of data completeness. For these cases it is concluded that the consistency can be assessed when the sea state is not too extreme. The method may be improved by using higher fidelity seakeeping codes.
Linking experimental and numerical wave modelling Sanne van Essen, Jule Scharnke, Tim Bunnik, Bülent Düz, Henry Bandringa, Rink Hallmann, Joop Helder Journal of Marine Science and Engineering, 2020
Sensitivity analysis in parametric rolling of a modern cruise ship using numerical simulations in 6-DOF Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering OMAE, 2020
Comparison of the CFD results to PIV measurements in kinematics of spilling and plunging breakers Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering OMAE, 2020
An absorbing boundary condition for free surface water waves 9th International Conference on Computational Fluid Dynamics Iccfd 2016 Proceedings, 2016
Efficient and accurate PLIC-VOF techniques for numerical simulations of free surface water waves 9th International Conference on Computational Fluid Dynamics Iccfd 2016 Proceedings, 2016
Locally-refined free-surface flow simulations for moored and floating offshore platforms Proceedings of the International Offshore and Polar Engineering Conference, 2016
Free-surface flow simulations for moored and floating offshore platforms Arthur Veldman, Roel Luppes, Peter Van Der Plas, Henri Van Der Heiden, Bulent Duz, Henk Seubers, Joop Helder, Tim Bunnik Eccomas Congress 2016 Proceedings of the 7th European Congress on Computational Methods in Applied Sciences and Engineering, 2016
Simulations of wave impact and two-phase flow with comflow: Past and recent developments Proceedings of the International Offshore and Polar Engineering Conference, 2013
The effect of different volume-of-fluid (VOF) methods on energy dissipation in simulations of propagating waves Computational Methods in Marine Engineering V Proceedings of the 5th International Conference on Computational Methods in Marine Engineering Marine 2013, 2013
Numerical simulations of two-phase flowwith comflow: Past and recent developments Eccomas 2012 European Congress on Computational Methods in Applied Sciences and Engineering E Book Full Papers, 2012
An absorbing boundary condition for regular and irregular wave simulations Marine 2011 Computational Methods in Marine Engineering IV, 2011
Numerical simulation of extreme wave impact on offshore platforms and coastal constructions Marine 2011 Computational Methods in Marine Engineering IV, 2011
Extreme wave impact on offshore platforms and coastal constructions Arthur E. P. Veldman, Roel Luppes, Tim Bunnik, Rene´ H. M. Huijsmans, Bulent Duz, Bogdan Iwanowski, Rik Wemmenhove, Mart J. A. Borsboom, Peter R. Wellens, Henri J. L. van der Heiden, Peter van der Plas Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering OMAE, 2011
RECENT SCHOLAR PUBLICATIONS
Data-driven prediction of ship heel in turns AB Bayezit, B Düz, R Tonelli, ÖK Kınacı, B Mak, V Ferrari Ocean Engineering 356, 125201 , 2026 2026
Experimental optimisation of the man overboard manoeuvre BJ de Kruif, B Düz, V Ferrari Applied Ocean Research 160, 104603 , 2025 2025
Ship trajectory prediction using encoder–decoder-based deep learning models B Düz, E van Iperen Journal of Location Based Services 19 (2), 146-166 , 2025 2025 Citations: 9
Predicting the dynamics of a gas pocket during breaking wave impacts using machine learning R Ezeta, B Düz Ocean Engineering 321, 120321 , 2025 2025 Citations: 2
Ship course-keeping in waves using sample-efficient reinforcement learning J Greep, AB Bayezit, B Mak, D Rijpkema, ÖK Kınacı, B Düz Engineering Applications of Artificial Intelligence 141, 109848 , 2025 2025 Citations: 4
General reinforcement learning control for AUV manoeuvring in turbulent flows AK Lidtke, D Rijpkema, B Düz Ocean Engineering 309, 118538 , 2024 2024 Citations: 15
Autonomous Sailing with Sim-to-Real Reinforcement Learning KJA Bink, GD Weymouth, B DUZ Available at SSRN 5339032 , 2024 2024 Citations: 4
A generalized reinforcement learning based controller for course-keeping of ships in waves A Bayezit, Ö Kinaci, B Düz, D Rijpkema, B Mak CIMNE , 2023 2023 Citations: 2
Combining deep reinforcement learning and computational fluid dynamics for efficient navigation in turbulent flows AK Lidtke, D Rijpkema, B Duz 10th Conference on Computational Methods in Marine Engineering , 2023 2023 Citations: 1
Quantifying uncertainties in numerical predictions of dynamic cavitation E Kara, AK Lidtke, B Düz, D Rijpkema, O Kemal Uncecomp2023 Proceedings, 599-620 , 2023 2023 Citations: 2
Consistency Assessment of Wave Directional Spectrum Predictions From Machine Learning Based Ship-As-a-Wave-Buoy Methods TP Scholcz, B Düz, RB Hageman, B Mak International Conference on Offshore Mechanics and Arctic Engineering 85901 … , 2022 2022 Citations: 6
Mitigating Spurious Low-Frequency Waves in a Model Basin With a Ramped Floor B Düz, J Scharnke, J de Wilde International Conference on Offshore Mechanics and Arctic Engineering 85901 … , 2022 2022 Citations: 2
Uncertainty quantification in the prediction of cavitation inception of the Duisburg Propeller Test Case AR Scussel, AK Lidtke, B Düz, D Rijpkema 24th Numerical Towing Tank Symposium , 2022 2022
Estimating parameter and discretization uncertainties using a laminar–turbulent transition model ET Katsuno, AK Lidtke, B Düz, D Rijpkema, JLD Dantas, G Vaz Computers & Fluids 230, 105129 , 2021 2021 Citations: 12
Sensitivity analysis in parametric rolling of a modern cruise ship using numerical simulations in 6-DOF B Düz International Conference on Offshore Mechanics and Arctic Engineering 84324 … , 2020 2020 Citations: 5
Comparison of the CFD results to PIV measurements in kinematics of spilling and plunging breakers B Düz, J Scharnke, R Hallmann, J Tukker, S Khurana, K Blanchard International Conference on Offshore Mechanics and Arctic Engineering 84386 … , 2020 2020 Citations: 4
A comparison of numerical simulations and model experiments on parametric roll in Irregular Seas G Kapsenberg, C Wandji, B Duz, S Kim Journal of Marine Science and Engineering 8 (7), 474 , 2020 2020 Citations: 17
Linking experimental and numerical wave modelling S van Essen, J Scharnke, T Bunnik, B Düz, H Bandringa, R Hallmann, ... Journal of Marine Science and Engineering 8 (3), 198 , 2020 2020 Citations: 21
Real time estimation of local wave characteristics from ship motions using artificial neural networks B Duz, B Mak, R Hageman, N Grasso Practical Design of Ships and Other Floating Structures, 657-678 , 2019 2019 Citations: 51
Ship as a wave buoy: Estimating relative wave direction from in-service ship motion measurements using machine learning B Mak, B Düz International conference on offshore mechanics and arctic engineering 58882 … , 2019 2019 Citations: 61
MOST CITED SCHOLAR PUBLICATIONS
Ship as a wave buoy: Estimating relative wave direction from in-service ship motion measurements using machine learning B Mak, B Düz International conference on offshore mechanics and arctic engineering 58882 … , 2019 2019 Citations: 61
Extreme wave impact on offshore platforms and coastal constructions AEP Veldman, R Luppes, T Bunnik, RHM Huijsmans, B Duz, B Iwanowski, ... International Conference on Offshore Mechanics and Arctic Engineering 44397 … , 2011 2011 Citations: 53
Real time estimation of local wave characteristics from ship motions using artificial neural networks B Duz, B Mak, R Hageman, N Grasso Practical Design of Ships and Other Floating Structures, 657-678 , 2019 2019 Citations: 51
Turbulence modeling, local grid refinement and absorbing boundary conditions for free-surface flow simulations in offshore applications AEP Veldman, R Luppes, HJL van der Heiden, P van der Plas, B Düz, ... International Conference on Offshore Mechanics and Arctic Engineering 45400 … , 2014 2014 Citations: 29
Ship as a wave buoy: Using simulated data to train neural networks for real time estimation of relative wave direction B Mak, B Düz International Conference on Offshore Mechanics and Arctic Engineering 58882 … , 2019 2019 Citations: 27
Linking experimental and numerical wave modelling S van Essen, J Scharnke, T Bunnik, B Düz, H Bandringa, R Hallmann, ... Journal of Marine Science and Engineering 8 (3), 198 , 2020 2020 Citations: 21
An absorbing boundary condition for regular and irregular wave simulations B Düz, RHM Huijsmans, AEP Veldman, MJA Borsboom, PR Wellens MARINE 2011, IV International Conference on Computational Methods in Marine … , 2013 2013 Citations: 19
An absorbing boundary condition for free surface water waves B Düz, MJA Borsboom, AEP Veldman, PR Wellens, RHM Huijsmans Computers & Fluids 156, 562-578 , 2017 2017 Citations: 18
A comparison of numerical simulations and model experiments on parametric roll in Irregular Seas G Kapsenberg, C Wandji, B Duz, S Kim Journal of Marine Science and Engineering 8 (7), 474 , 2020 2020 Citations: 17
General reinforcement learning control for AUV manoeuvring in turbulent flows AK Lidtke, D Rijpkema, B Düz Ocean Engineering 309, 118538 , 2024 2024 Citations: 15
Towards a general-purpose open boundary condition for wave simulations B Duz, RHM Huijsmans, PR Wellens, MJA Borsboom, AEP Veldman International Conference on Offshore Mechanics and Arctic Engineering 44397 … , 2011 2011 Citations: 13
Estimating parameter and discretization uncertainties using a laminar–turbulent transition model ET Katsuno, AK Lidtke, B Düz, D Rijpkema, JLD Dantas, G Vaz Computers & Fluids 230, 105129 , 2021 2021 Citations: 12
Numerical simulation of nonlinear free surface water waves: Coupling of a potential flow solver to a URANS/VOF code B Düz, T Bunnik, G Kapsenberg, G Vaz International Conference on Offshore Mechanics and Arctic Engineering 49934 … , 2016 2016 Citations: 12
Ship trajectory prediction using encoder–decoder-based deep learning models B Düz, E van Iperen Journal of Location Based Services 19 (2), 146-166 , 2025 2025 Citations: 9
Wave-in-deck impact loads in relation with wave kinematics J Scharnke, R Lindeboom, B Duz International Conference on Offshore Mechanics and Arctic Engineering 57656 … , 2017 2017 Citations: 9
Simulations of wave impact and two-phase flow with ComFLOW: past and recent developments R Luppes, HJL van der Heiden, P van der Plas, AEP Veldman, B Düz ISOPE International Ocean and Polar Engineering Conference, ISOPE-I-13-393 , 2013 2013 Citations: 8
Comparison of breaking wave kinematics from numerical simulations with PIV measurements B Düz, R Lindeboom, J Scharnke, J Helder, H Bandringa International Conference on Offshore Mechanics and Arctic Engineering 57748 … , 2017 2017 Citations: 7
Numerical simulation of extreme wave impact on offshore platforms and coastal constructions R Luppes, B Duz, HJL van der Heiden, P van der Plas, AEP Veldman Proc. 5th Conf. on Computational Methods in Marine Engineering MARINE 2011 , 2011 2011 Citations: 7
Consistency Assessment of Wave Directional Spectrum Predictions From Machine Learning Based Ship-As-a-Wave-Buoy Methods TP Scholcz, B Düz, RB Hageman, B Mak International Conference on Offshore Mechanics and Arctic Engineering 85901 … , 2022 2022 Citations: 6
Efficient and accurate PLIC-VOF techniques for numerical simulations of free surface water waves B Duz, MJA Borsboom, AEP Veldman, P Wellens, R Huijsmans Proceedings of the 9th International Conference on Computational Fluid … , 2016 2016 Citations: 6
