Optimisation of passenger ship structures in concept design stage. (3rd October 2019)

• Record Type: Journal Article
• Authors: Raikunen, Joni; Avi, Eero; Remes, Heikki; Romanoff, Jani; Lillemäe-Avi, Ingrit; Niemelä, Ari
• Is Part Of: Ships and offshore structures. Volume 14(2019)Supplement 1
• Page Start: 320
• Page End: 334
• Publication Date: 2019-10-03
• Subjects: Optimisation -- equivalent single layer (ESL) theory -- equivalent element -- particle swarm optimisation -- global finite element model -- passenger ship -- constraint relaxation; Ships -- Periodicals; Offshore structures -- Periodicals; Marine engineering -- Periodicals; Marine engineering -- Technological innovations -- Periodicals; Ocean engineering -- Periodicals; Ocean engineering -- Technological innovations -- Periodicals; 623.8
• DOI: 10.1080/17445302.2019.1590947
• Languages: English
• ISSNs: 1744-5302

Abstract

ABSTRACT: This paper presents an optimization method for concept design state of passenger ship with focus on utilisation of efficient Finite Element Modelling, evolutionary optimisation algorithm and indirect constraint relaxation. The response is analysed using 3D coarse mesh global finite element (FE) model, where stiffened panels are modelled using equivalent single layer (ESL) elements and the primary stiffeners are modelled with offset beam elements. The simplifications on stiffened panels and beams enable exploration of design space without changing the FE-mesh. The strength is defined based on classification society rules. Local stress peaks are allowed to exceed the rule-based strength limits, i.e. stress constraints are relaxed indirectly. Instead of increasing the allowed stress levels, the amount of material exceeding strength criteria is utilised. Optimization is based on Particle Swarm Optimization (PSO) algorithm with objective to reduce steel weight. The results show that stress relaxation has significant effect on the obtained total mass.