Automated CFD-based optimization of inverted bow shape of a trimaran ship: Proposing an applicable and efficient optimization platform

Document Type : Research Note

Authors

1 Dept. of Maritime Engineering, Amirkabir University of Technology, Tehran, Iran

2 Department of Maritime Engineering, Amirkabir University of Technology, Tehran, Iran

10.24200/sci.2020.56644.4833

Abstract

This paper investigates the improvement of bow region of a trimaran ship hull, proposing a CFD-based automated approach to reduce total resistance. Two main goals are pursued; to create and develop a useful optimization platform for ship hull modification, and then investigate the influence of different inverted bow on hydrodynamic performance of trimaran ship. A wave-piercing bow trimaran hull is the baseline design. Ship bow is redesigned by Arbitrary Shape Deformation (ASD) technique that defines the input variables for optimization process. The objective function is the drag force and this study is conducted at cruise speed. To accomplish this task, two optimization methods are sequentially applied. A Latin Hypercube Sampling tool distributes design points and an RBF based surrogated model is constructed to investigate system behavior. Final optimum design in Design of Experiment (DOE) study is introduced to direct optimization SHERPA algorithm. Integration of CFD solver, geometric parametrization, and optimizer tool is managed by HEEDS MDO package with a multi-connection approach. Optimization results show successful optimization along with 10.2% resistance reduction. Comparison between initial and optimized hull demonstrates that the proposed optimization platform can be used for ship hull optimization in industrial application with significantly reduced computational time and effort.

Keywords