Early Structural Assessment and Optimisation of Passenger Ships

peer reviewedA multi-criteria optimisation of a passenger ship is conducted in this paper. Minimum production cost and minimum steel weight are the both objective studied. Moreover the study answers to the following question: "From when will the higher costs of high tensile steel should be offset by a gain of steel weight?". For a passenger ship, a significant reduction of the steel weight, for a controlled raise of the gravity centre, should lead either to a reduction of fuel consumption either to an additional deck, which for a ship owner means a faster return on investment. Pareto frontiers are obtained and results are validated by classification rules

Optimization of Shipyard Space Allocation and Scheduling using Heuristic Algorithm

In this paper we describe the development of a tool that allows planners to efficiently and effectively plan space within valuable areas of a shipyard. Traditionally, space is considered as resource; however, it is difficult to accurately account for and plan its consumption with the current planning software tools available. The spatial scheduling tool described in this paper can be used by planners to manually or automatically reserve space within the shipyard for construction of large blocks over the entire ship erection period. The software is coupled with a heuristic optimization solver which is inspired by an algorithm used for "3D bin-packing problems". The result is the ability to efficiently generate and compare multiple space allocation alternatives in a reduced time with the ultimate goal of maintaining the critical ship erection schedule. Better solution than manual or semi-automatic allocation of blocks can be obtained through the optimization module

Weather Down Time Analysis for Offshore Wind Farm Installations

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Multicriterion Scantling Optimization of the Midship Section of a Passenger Vessel considering IACS Requirements

peer reviewedIn the scantling design of a passenger ship, minimum production cost, minimum weight and maximum moment of inertia (stiffness) are conflicting objectives. For that purpose, recent improvements were made to the LBR-5 software (French acronym of “Stiffened Panels Software”, version 5.0) to optimize the scantling of ship sections by considering production cost, weight and moment of inertia in the optimization objective function. Moreover, IACS requirements regarding bending, shearing and buckling strength are currently available in LBR-5. Until now, only raw scantling optimizations were performed with LBR-5. Thanks to new developments using heuristics, it is now possible to realize discrete optimization so that a standardized and “ready to use” set of optimum scantlings can be obtained

Tools for early design stage: presentation of LBR-5 Software

peer reviewedLBR-5 is a tool for early design stage. Taking into account numerous kinds of constraints – structural, geometrical, etc. – an optimum scantling can quickly been found. In the framework of IMPROVE European project many new modules have been implemented to increase the quality of the optimised scantling. Mainly 6 major changes have been brought: implementation of a sloshing module, a fatigue module, a multi-structure module, a multi-materials module, a life cycle cost module and finally a vibration module. Tests to validate these modules have been carried out on the three ships studied in the IMPROVE project: a LNG, a Chemical Tanker and a ROPAX

Linking design and production in computer applications for increased efficiency

Shipbuilding has been severely affected by the global economic crisis. Demand for new ships has collapsed world wide since summer 2008 causing an unprecedented levels of overcapacity in the global cargo ship fleets. The current crisis gives impulses for a radical think to adopt new designs to reduce the life cycle costs and to decrease the environmental impact. Leading shipping companies recognise that low life cycle cost and low emission save costs, open quality sensitive markets and will be the key driver to profitability in the future. The speaker will present some possible techniques to improve the link between design and production in order to boost the competitiveness of worldwide shipyards. Modularizations, ease of manufacturing, standardization, virtual reality, production simulation, product life cycle management, are some of these techniques illustrated in the presentation. The speaker will also draw the trends for the future years

Recensement et Caractérisation des Pièces Constitutives de la Structure Métallique d'un Navire à Passagers, sous la Double Vision : Produit Fini – Méthode de Production

Le prix de revient de la structure métallique d'un navire réside principalement dans la main d'oeuvre nécessaire à l'assemblage des pièces et éléments constitutifs. Deux gisements importants de réduction de ce prix sont : - minimiser le coût inhérent à chaque opération (mécanisation, outillages, méthodes, précision, formation ouvrier, ...) ; - minimiser le nombre de ces opérations en diminuant le nombre d'éléments à assembler. Aux Chantiers de l’Atlantique, le premier axe fait depuis plusieurs années l'objet de nombreuses actions et on souhaite aujourd'hui explorer plus avant le second thème. Avant d'envisager la faisabilité et la rentabilité d'actions fortes dans ce domaine, une étape préliminaire visant à établir une connaissance plus fine des éléments constitutifs est nécessaire, c'est à cette première phase que nous avons apporté notre contribution. L’objectif de l'étude est d’établir un recensement et une caractérisation des pièces constitutives de la structure métallique d'un navire à passagers afin de mettre en lumière, le cas échéant, les gisements potentiels d’économie. Deux axes d’études ont été choisis. Le premier s’oriente vers une analyse du « produit fini », le second s’oriente vers la « phase de production ». Il s’agit plus précisément, pour l’analyse du « produit fini » de recenser et caractériser en nombre, en masse, en distribution géographique et en niveau de sollicitation, les pièces constitutives des grandes familles structurelles d’un paquebot de référence choisi parmi les plus récents. Par exemple, il sera question de quantifier le nombre et le poids des pièces constituant les ponts. Par contre, pour l’analyse orientée vers la « phase de production », il s’agit de déterminer et de repérer à quel stade de production les pièces du pont sont montées et vérifier la pertinence de leur lieu de montage. Par exemple, il sera question de quantifier le nombre et le poids des pièces constituants chaque panneau. En final, nous proposons des pistes d’investigation visant à réduire le nombre de pièces constructives s’intégrant dans la structure métallique des paquebots et à en fournir tous les éléments nécessaires à leur analyse