Hydrodynamic Optimization of Ship Hull with Multi-objective Optimization Algorithms

Supervisor

Prof. Dr.-Ing. Bettar Ould el Moctar

Author

Yanxin Feng, M. Eng.

Description

The International Maritime Organization (IMO) requires that all new ships meet minimum energy efficiency levels according to the Energy Efficiency Design Index (EEDI). This requirement can be satisfied by reducing emissions, a measure that also decreases fuel costs. To reach this goal, optimizing the ship’s hull for least resistance became a relevant design issue because hull shape significantly affects the ship’s performance. Successful optimization involves the geometric variation of the hull form. Combined with CFD methods, we applied a computer aided design (CAD) method to parametrically model and subsequently optimize the hull shape of containership with different sizes.

This thesis describes the following research work:

  • Using a CAD-system (e.g. CAESES), a prametric hull for containership DTC has been created with fully-parametric modelling method.
  •  Combining with a potential flow solver (e.g. GLRankine) to simulate the prediction of the resistance and motions in both calm water and wave conditions.
  • Applying the parametric hull to different sizes of containership (KCS and S175) by changing parameters.
  • Numerical prediction of resistance and motions are validated by experimental data.
  • Three multi-objective optimization algorithms (MOSA, NSGA-II, and SBGO) are used to minimize the resistance and improve the seakeeping performance of objective hull form.
  • The optimized results are analyzed and compared to get the optimal hull form.

Results examples

As examples, the following figures show part of results of the optimization for DTC.

Feng2

 

Publications

  • Feng, Yanxin, Ould el Moctar, and Thomas E. Schellin.
    "Hydrodynamic Optimisation of a Multi-purpose Wind Offshore Supply Vessel."
    Ship Technology Research 67.2 (2020): 69-83.
  • Feng, Yanxin, Ould el Moctar, and Thomas E. Schellin.
    "Hydrodynamic Optimization of a Containership."
    In International Conference on Offshore Mechanics and Arctic Engineering, vol. 84331, p. V02BT02A017. American Society of Mechanical Engineers, 2020.
  • Feng, Yanxin, Ould el Moctar, and Thomas E. Schellin.
    "Parametric Design and Optimization of Three Containerships".
    (under work)

Funding

Feng1
This research was funded by the University Postgraduate Program ([2013]3009) through the China Scholarship Council [N201306250034].