@conference{
author = "Vasilev, Matija and Kalajdžić, Milan and Suvačarov, Aleksa",
year = "2023",
abstract = "The bulbous bow is a significant feature integrated into ship designs to improve their overall
performance. However, relying solely on original design assumptions may lead to suboptimal results,
potentially hindering the vessel's efficiency during operation. To address this issue and optimize ship
performance, this paper proposes a practical methodology for retrofitting the bulbous bow to suit the
actual operational profile of container ships. By analyzing four years' worth of operational data, this
study identifies the most frequent sailing conditions, including speed, draft, trim, and displacement.
Using this information, multiple bulbous bow configurations by following Kracht (1978) are derived
and subjected to numerical simulations, tailored to various sailing conditions. The proposed framework
not only optimizes the bulbous bow for container ships but also extends its application to other vessel
types such as bulk carriers, tankers, and large commercial ships. By customizing the bulbous bow design
to match specific operational profiles, significant improvements in fuel efficiency, environmental
sustainability, and overall operational performance can be achieved. This research underscores the
significance of accounting for real-world operational conditions when designing and optimizing the
bulbous bow. Leveraging operational data and conducting numerical simulations facilitates the
identification of optimal configurations, aligning vessel performance with its actual sailing conditions.
Implementing these optimized bulbous bow designs has the potential to revolutionize the maritime
industry by enhancing ship performance and promoting energy efficiency. By prioritizing the practical
considerations of real-world operational conditions, this paper presents a valuable approach to improve
the overall efficiency of ships, contributing to a more sustainable and eco-friendly maritime sector. CFD,
or Computational Fluid Dynamics, has revolutionized the process of bulb optimization. Before its
introduction, research was primarily based on physical model testing. However, CFD has made it
significantly easier and faster to refine bulb designs. This technological advancement has allowed for
the incorporation of economic and ecological considerations into bulb design, going beyond just
hydrodynamics (refer to Schneekluth et al 1998). This advancement enables engineers and designers to
not only improve the hydrodynamic performance of the bulb, but also to take into account factors such
as cost-effectiveness and environmental impact. As a result, bulb optimization has become a more
comprehensive and efficient process, ultimately leading to better-designed vessels and a more
sustainable approach to shipbuilding. The first serious attempts to improve ship design using CFD
began during the previous decades which includes parametric design Lu et al (2016), Yang et al (2016),
Peri et al (2001), Sharma et al (2008), Wagner et al (2014) and many others. A common characteristic
among all of them is that the bulbous bow has a positive effect at higher speeds (refer to Schneekluth
et al (1998)). In this paper, bulb optimization is presented as a measure to improve the energy efficiency
of a container vessel in order to meet the Carbon Intensity Indicator (CII) criteria defined in Resolution
MEPC.353(78) (2022). The concept of a CII within the shipping industry, designed to gauge and
manage the carbon emissions associated with maritime activities, has emerged as a crucial tool in
addressing environmental concerns and reducing the sector's carbon footprint. The aim of the measures
is to improve the fleet average carbon intensity by at least 40% in 2030, relative to 2008 (refer to
Resolution MEPC.377(80), (2023)).",
publisher = "blueOASIS – Ocean Sustainable Solutions",
journal = "NuTTS 2023 25th Numerical Towing Tank Symposium 15 – 17 October 2023. Ericeira, Portugal",
title = "A Practical Approach to Bulbous Bow Retrofit Analysis for Enhanced Energy Efficiency",
url = "https://hdl.handle.net/21.15107/rcub_machinery_7627"
}
