Design optimization of composite submerged cylindrical pressure hull using genetic algorithm and finite element analysis

• Published in: Ocean engineering 2019-10, Vol.190, p.106443, Article 106443
• Main Authors: Imran, Muhammad, Shi, Dongyan, Tong, Lili, Waqas, Hafiz Muhammad
• Format: Article
• Language: English
• Subjects: Buckling strength factor; Buoyancy factor; Composite failure criteria; Design optimization; Genetic algorithm; Submerged pressure hull
• ISSN: 0029-8018; 1873-5258
• DOI: 10.1016/j.oceaneng.2019.106443

The design of structures made of laminated composites greatly depends on the fiber orientation angle and the number of ply layers. In the present study design optimization of composite submerged pressure hull under 3 MPa hydrostatic pressure, which corresponds to 300 m depth, is carried out. The number of layers and orientation angles are optimized for layups [0m/90n/0o], [10m/-10n/90o/-10p/10q], [α1m/α2n], [α1m/α2n/α3o] and [α1m/α2n/α3o/α4p/α5q] using three unidirectional composite materials, Carbon/Epoxy, Glass/Epoxy, and Boron/Epoxy. The optimization process is carried out in ANSYS Workbench using a Genetic Algorithm. Minimizing the buoyancy factor is used as the objective function of the optimization. The constraints on the optimization process are Tsai-Wu and Tsai-Hill failure criteria and buckling strength factor. Optimization study is also conducted for one selected layup configuration using ABAQUS and ISIGHT. Additionally, a sensitivity analysis is also carried out to study the effect of various design parameters on the optimum design of composite submerged pressure hull. •Design optimization of composite submersible cylinderical pressure hull is conducted using a genetic algorithm and finite element analysis.•The number of layers and orientation angles are optimized for five layup configurations using three unidirectional composite materials.•A sensitivity analysis is also conducted to investigate the effect of design variables on one selected optimum layup configuration.•It is demonstrated that the optimum design not only depends on the ply orientation but also on the number of ply layers.•A maximum improvement ratio of 62.344% in the buoyancy factor over similar steel hull is obtained for Carbon/Epoxy.