Comparative assestment of the effect of changing the breadth (b) of the ship on the stability of the tugboat

This paper reviews the effect of changing the breadth of a tugboat before and after production on ship stability. The numerical simulation method (maxurf stability) is applied. Likewise, another approach uses the Benjamin Spence (integrator) method. The standard used is IMO. Several limits become parameters for assessing the increase and decrease in ship stability. Several ship load cases are simulated to produce righting arm curves. The construction of a tugboat with a length of 28 meters is the object of this research as a case study. We compared the righting arm curve from the Maxurf stability analysis with Benjamin Spence's analysis to confirm the accuracy of the calculation results. Both methods show a significant influence regarding changes in the breadth of the tugboat. The produced righting arm curve consistently shows changes in the stability and performance of the ship. There is a reduction in the area under the GZ curve. The IMO provides three of the five standards and recommendations regarding the area under the GZ curve. The reduction of the area under the GZ curve is 17~22% for the Benjamin Spence method and 12~18% for the Maxurf stability. This percentage applies to all load-case simulations. This research contributes to providing an understanding of the effect of changes in ship width on decreasing stability.

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1. Pełne imiona podano na stronie internetowej czasopisma w "Author index" lub "Authors in other databases."

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2. Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2025).