Multiple speed integrated optimization design for a SWATH using SBD technique

Hull geometry modification and reconstruction, optimization algorithms and CFD technique are combined together into what is known as simulation-based design (SBD) techniques, and its essence is the hydrodynamic configuration design driven by global flow optimization. The purpose of this paper is to show how the improvement in the hydrodynamics performance of a Small Waterplane Area Twin Hull (SWATH) can be obtained by solving a shape optimization design problem at different speeds using the SBD technique. In this paper, an example of the technique application for the SWATH hull-form optimization at different speeds is demonstrated. In the procedure, the free-form deformation method is chosen to automatically modify the geometry of submerged pontoon, and the multi-objective particle swarm optimization (MOPSO) algorithm is adopted for exploring the design space. The two objectives functions, the total resistance at two different speeds (11 kn and 15 kn), are assessed by RANS solvers. The optimization results show that the decrease in total resistance is significant for the optimization case at two different speeds (11 kn and 15 kn), with a reduction of about 5.1% and 6.3%, respectively. Meanwhile, the displacement increases 3.7% and the transverse section of submerged pontoon becomes “flower vase” type from ellipse. Finally, dedicated experimental campaigns for optimized model have been carried out to validate the computations and establish the effects of the optimization processes. It shows that the computations of optimization scheme mainly fit the results of model test. The given, practical examples demonstrate the practicability and superiority of the proposed SBD technique for the SWATH multiple speed integrated optimization problem. In addition, the technique can also be applied to other fields of shape optimization design.

[1]  Thomas W. Sederberg,et al.  Free-form deformation of solid geometric models , 1986, SIGGRAPH.

[2]  Giuliano Vernengo,et al.  Concept design and hydrodynamic optimization of an innovative SWATH USV by CFD methods , 2011, Ocean Dynamics.

[3]  Andrea Serani,et al.  Resistance and Payload Optimization of a Sea Vehicle by Adaptive Multi-Fidelity Metamodeling , 2018 .

[4]  Shengzhong Li,et al.  Multiobjective Optimization for Ship Hull Form DesignUsing SBD Technique , 2013 .

[5]  Riccardo Poli,et al.  Particle swarm optimization , 1995, Swarm Intelligence.

[6]  Andrea Serani,et al.  Formulation and parameter selection of multi-objective deterministic particle swarm for simulation-based optimization , 2017, Appl. Soft Comput..

[7]  W SederbergThomas,et al.  Free-form deformation of solid geometric models , 1986 .

[8]  YU Xian-zhao.  The development and future trend of foreign SWATH ships , 2012 .

[9]  Feng Zhao,et al.  An integrated optimization design of a fishing ship hullform at different speeds , 2018 .

[10]  Chi Yang,et al.  An overview of simulation-based hydrodynamic design of ship hull forms , 2016 .

[11]  Daniele Peri,et al.  Numerical optimization methods for ship hydrodynamic design , 2010 .

[12]  Soonhung Han,et al.  Hydrodynamic hull form optimization using parametric models , 2012 .

[13]  Ho-Hwan Chun,et al.  Hull-form optimization using parametric modification functions and particle swarm optimization , 2016 .

[14]  Feng Zhao,et al.  Bow and Stern Shape Integrated Optimization for a Full Ship by a Simulation-based Design Technique , 2014 .

[15]  Daniele Peri,et al.  Single- and multiobjective design optimization of a fast multihull ship: numerical and experimental results , 2011 .

[16]  M. Diez,et al.  Design-space dimensionality reduction in shape optimization by Karhunen–Loève expansion , 2015 .