International Journal of Maritime Engineering

Experimental Testing of Riveted Carvel Planks on Frames for Traditional Timber Structures

Jean-Baptiste Souppez — 2025-01-03

Traditional wooden boats are characterised by closely spaced frames, riveted to thick planks, leading to high thickness-to-span ratios. However, the effect of such closely spaced frames and thickness-to-span ratio remains uncharacterised. Consequently, four-point bending tests are undertaken to quantify the ultimate flexural strength and flexural modulus of wooden planks with up to 3 frames and thickness-to-span ratios from 0.0267 to 0.200. The results show that (i) a greater number of frames for a given span yields a reduction in specific stiffness but a constant specific strength; (ii) a maximum thickness-to-span ratio of 0.080 and 0.050 is recommended to ensure the strength and stiffness exceed regulatory default properties, respectively, and (iii) additional factors of safety would be needed for traditional construction to be included in existing structural regulations. These findings provide novel insights into the structural design of traditional wooden boats and may contribute to their future inclusion in regulatory frameworks.

DIGITAL TWINS IN MARITIME SAFETY: A BREAKTHROUGH IN HULL STRUCTURAL INTEGRITY MONITORING VIA CUTTING-EDGE CONVERSION METHODS AND BASE MODE SELECTION ALGORITHMS

Do Kyun Kim — 2025-01-03

Maritime vessels constantly experience various environmental loads, leading to cumulative fatigue damage on their hull structures, which can ultimately result in structural failure. Despite existing efforts to measure these structural responses, limitations in both sensor availability and measurable hull data present significant challenges. This study presents a ground-breaking approach within the sphere of Digital Twins in Maritime Safety. Our novel conversion method uses limited sensor data to estimate comprehensive hull responses, introducing an innovative base mode selection algorithm for improved accuracy. Leveraging extensive data from the Magellan container ship, including strain gauge measurements and wave spectra, we validate our model's robustness. As a unique feature, we offer a stress contour for the complete non-watertight bulkhead, underscoring our model's spatial precision. This pioneering approach optimises the use of limited measurements, marking a transformative breakthrough in hull structural integrity monitoring.

Ms ENHANCEMENT OF HYDRODYNAMIC PERFORMANCE WITH ENERGY SAVING DEVICES FOR PLANING HULL

Suneela j — 2025-01-03

The moving planing vessel in transition mode dissipates most of the energy from hull to water in calm seas. Kelvin wave pattern is observed in calm water, which is strongly dependent on the Froude number. The results of numerical simulations are compared with experimental results, observed that the resistance of the vessel obtained from experiments for hull with interceptor is predicted closer to numerical results. The free surface of water is traced by the Volume of Fluid (VOF) method, using the overset grid method in RANSE based CFD solver. The results obtained were used to calculate the resistance components of a planing hull. The focus of this paper is to capture the resistance, trim and wave profile near the free surface at transom for different beam Froude numbers and is compared with and without integrated interceptor-flap on a high-speed planing craft with 20 deg deadrise angle. Reduction in drag, trim and the free surface wave elevation at transom is observed for the hull fitted with integrated interceptor-flap which helps further decrease in the wave resistance.

UNVEILING THE JOURNEY OF MARITIME ENERGY EFFICIENCY: A DEEP DIVE INTO EEDI, EEXI, CII, POTENTIAL CII REGULATION ENHANCEMENTS, AND PERSISTENT CHALLENGES

Nalin Baijal — 2025-01-03

The Energy Efficiency Design Index (EEDI) and the Energy Efficiency Existing Ship Index (EEXI), two crucial regulations in the maritime sector, are examined in detail in this paper. This study aims to understand the complexities of these restrictions and analyse how the Energy Efficiency Operational Indicator (EEOI) could be used to improve the way the maritime industry measures Carbon Intensity Indicator (CII).

This study offers insightful information on the regulatory environment governing energy efficiency in shipping by analysing the historical trajectory and transformation of the EEDI. It provides a thorough overview of the regulations now in effect, illuminating their tenets and guiding ideas.

Additionally, this study offers a path for prospective CII framework upgrades that goes beyond simple analysis. It investigates whether adding the EEOI is feasible and how it can improve the precision and applicability of emission measurement in the maritime industry.

In essence, this paper provides a comprehensive overview of the development of EEDI, the current regulatory landscape, and how creative modifications, such the inclusion of EEOI, could further improve existing methodologies to address the changing demands of sustainability in shipping.

PROPOSED AMENDMENTS IN SOLAS AND MARPOL CONVENTIONS TO LIMIT VOC EMISSION FROM OIL TANKER LOADING AND SHIP BUNKERING OPERATIONS

Satinder Virdi — 2025-01-03

Exhaust gas emissions are regulated at international and national levels, but venting vapours from oil tanks is a cause of concern due to a lack of regulatory control. Oil tanker loading operations and ship bunkering operation results in a considerable amount of 'Volatile Organic Compound' (VOC) in the surrounding environment. The presence of toxic components in this VOC emission has the potential to affect the health of seafarers as well as local air quality. Numerous tankers engaged in loading operations within the same port has a solid potential to increase the toxic emission to a dangerous level locally. Loading ports near highly populated areas expose the local population to toxic VOC concentration. A few ports in Europe, the USA and South Korea have strict local environmental rules prohibiting VOC emission from oil tanker loading operations. There is a need for international and national regulations to limit or stop the release of VOCs from oil tankers and monitor VOC exposure risks at the local level. The research objective is to analyse the current status of international and national rules and regulations related to VOC emission and monitoring VOC exposure risks during loading operations in an oil tanker and ship bunkering operations. Existing international (SOLAS and MARPOL Conventions) and national regulations (EU, USA, Norway) are described and analysed regarding the contemporary tanker design and standard tanker operating practice. A critical analysis determines the effectiveness and adequacy of the current regulations and tanker industry working practices. Finally, amendments to existing international conventions are proposed to minimise or stop the VOC emission and monitor VOC exposure risks to seafarers and the surrounding population near tanker terminals and ports. Solutions are also proposed to amend the existing tanker design and operating practices to stop the VOC emission, including toxic hazard assessment in vapour vent design and prevent exposure to VOC emission.