Master's thesis; State-of-the-art simulations of Mooring Line Arrangements for Merchant Ships

Background
Mooring of merchant ships [1] is regulated by the IMO SOLAS regulation II-1/3-8 [2]. It is of uttermost importance to safely moor ships in any given weather condition at a specific location.

However, given that a specific ship at a specific location can be subjected to a variety of different weather conditions, it can be difficult to know exactly what constitutes a safe and secure mooring arrangement, as different locations can require different arrangements due to possible weather conditions at that location.

Physical computer simulations are an excellent tool to evaluate different wind conditions and different mooring line arrangements for ships. However, the physical phenomena are both time-dependent and complex, involving phenomena such as fluid flow (air, water), fluid-structure (air – ship and water - ship) interactions and structural mechanics of non-linear and flexible lines as well as a large separation of the scales (both space and time).

A direct numerical approach of such a scenario is not feasible due to the computational resources it would require. Therefore, a simplification of the computational approach and mathematical models that reduces the computational cost but still give accurate enough results to be used in real world applications.

[1] https://www.imo.org/en/OurWork/Safety/Pages/SafeMooring.aspx

[2] https://wwwcdn.imo.org/localresources/en/Documents/MSC.1-Circ.1619 -.pdf

Description
The purpose of this thesis is to investigate the state-of-the-art of mooring simulations. Different approaches will be investigated, such as coupled CFD-FEM approaches as well lower-order semi-empirical rigid body dynamic formulations. The students are expected to define a suitable test case based on an initial literature study and carry out simulations comparing different simulation tools to experimental measurements of line tensions found in the literature.

Key Responsibilities
The students will have to thoroughly understand and formulate the problem from a physical and naval architecture perspective, as well as from a computational perspective, describing the different simulation methods and their assumptions and restrictions. They will get hands on experience from simulation tools that are used in both commercial and research project within the maritime industry.

The thesis will be carried out within the simulation group at RISE Maritime department. The group consists of simulation experts and has a long experience in ship dynamics simulation for different applications such as mooring analysis, seakeeping and maneuvering.

Qualifications
Suitable for 1-2 students from Naval Architecture, Applied Mechanics or Engineering Mathematics and Computational Science or similar master’s programs with a strong interest in numerical simulations within naval architecture. Interest and skills in programming (python, C++) is advantageous but not a requirement.

The extent of the thesis is 30 HP per student. The thesis is expected to start in January 2025 and be finished by June 2025. The compensation will be 30 000 SEK per person. 

Terms
The students will be provided office space at RISE Maritime offices on Chalmers Campus in Gothenburg and will be co-supervised by:

Dr. Mohsen Irannezhad:

From June 2024 Dr. Irannezhad works in the simulation group within Maritime Consulting at RISE Maritime. He focuses on ship dynamical simulations concerning e.g. mooring analysis, seakeeping and maneuvering, as well as software development of the in-house ship dynamics software library SEAMAN. He completed the Naval Architecture and Ocean Engineering Master’s program at Chalmers in 2017. He then worked at the Division of Marine Technology at Chalmers focusing on seakeeping performance of a ships in waves. In March 2024, he defended his PhD thesis titled “Propeller-Hull Interaction Effects in Calm Water and Regular Head Waves” from the same division.

Dr. Jan Östh:

Dr. Östh works in the simulation group within Maritime Consulting at RISE Maritime since August 2022. There he focuses on software development of the in-house ship dynamics software SEAMAN. SEAMAN is used in both commercial and research projects within RISE Maritime in applications such as Mooring analysis, Seakeeping, maneuvering, RISE Maritime’s web-application Seaman Online and the full mission maneuvering simulator.

Dr. Östh holds BSc (Engineering Physics, 2008), MSc (Applied Mechanics, 2010) and PhD (thermo and fluid mechanics) degrees from Chalmers University of Technology, he also has over 6 years of experience as industrial consultant and consultant management within CFD in various industries prior to joining RISE Maritime.

Welcome with your application!
Applications should include a brief personal statement, a CV, and a list of grades. The application should mention previous activities or other projects that are relevant for the position. Candidates are encouraged to send in their application as soon as possible. Suitable applicants will be interviewed as applications are received. Last day of application is November 11, 2024. For more information, please contact mohsen.irannezhad@ri.se or jan.osth@ri.se