Enginsoft enables composite material analysis

Edited by the Engineeringtalk editorial team Mar 18, 2009

The Enginsoft group has developed a procedure for the study, analysis, design and optimisation of structures made of composite material.

This procedure, which utilises Modefrontier capabilities, allows complete integration of the ESAComp software for the design of composite materials with the Ansys code for finite elements, within the design and multi-objective optimisation environment, produced by Esteco.

The implemented routine allows generation of the foil sequence associated with any kind of rolled section, leaving Modefrontier to decide upon the number, orientation and the kind of rolled sections that constitute the composite.

The examined rolled sections are automatically transferred to the finite element model, processed though the Ansys environment, which aims to analyse the behaviour of the structure or the system it is part of.

The process keeps automatically repeating until the optimum solutions are achieved and/or till the design criteria are completely satisfied.

A test case using this routine involved the study and structural optimisation of the hull of a sailing race boat (a 35ft IMS), through the generation, analysis and optimisation of the rolled sections.

Modefrontier managed the dynamic generation of the rolled section configurations applied to the boat.

In particular, the variables implemented and optimised by the software were: the rolled section number; the fibre orientation; different material fibres; the use of sandwich structures or full rolled sections; the kind of material used for the core; and the core location within the rolled section.

The different parts of the boat hull underwent a preliminary design through ESAComp, aiming at the identification of the project variable values to guarantee the fixed objective achievements (weight and material cost reduction, performance maximisation, and so on).

The complete hull model, to which a new rolled section configuration (suggested by ESAComp) had been applied, was structurally analysed through Ansys, with the aim of evaluating if the tension and deformation fields, related to the different parts, came into the project specification.

In this way, the composite materials that made up the boat were optimised through a structural and material analysis, verified with ESAComp.

The rolled sections in question had to suit the requirements set by the Italian Naval Register (RINA), which also uses this software for its evaluations.

The automatic management of the software within Modefrontier allows for the search for optimum solutions to simultaneously satisfy the different objectives and constraints defined by both applications.

The analysis focused on four parts of the boat: deck, hull, frame floors and internal structures.

The preliminary analysis, aiming at the identification of loads, boundary conditions and test materials, highlighted the crucial stress areas of the boat.

The frame floors, in particular, proved to be the most critical element, pointing out a considerable stress.

The second phase of the project shifted to the real optimisation of the boat.

The constraints were applied to the deck and the internal structures, in a way to not make them suffer a stress exceeding the failure criterion, while the hull and frame floor composite materials were optimised.

Modefrontier managed the two rolled section lay-up (the one for the hull and the other for the interior), and in particular, the kind and the orientation of the materials used for the rolled section layers.

In the third phase, one more constraint was applied to the frame floor and hull stress, paying special attention to the optimisation of the rolled sections used for internal structures and for the deck.

Importing the data regarding the rolled section from Modefrontier, ESAComp carried out a conformity analysis in compliance with the RINA specification and then exported the two rolled sections to Ansys to have them applied to the FEM model.

Ansys worked out a structural analysis of the model, providing Modefrontier with the optimisation results.