In modern engineering, coupled multiphysics are more and more taken into account to model and simulate physical phenomena. In many problems mechanical mechanism are induced or strongly influenced by alternative physical mechanisms. Various examples or coupled formulations of thermo-hydro mechanics of porous media are presented in [1]. An example of a study to model the behaviour of wood during the drying process is described in [2]. Similar examples exist in various fields including: bio-engineering and materials processing (e.g. composites, paper manufacturing). The growing interest in strongly coupled multiphysics in different fields raises the problem of the integration of these complex models into simulation software. The simplest and most usual way to develop computational tools is either to use industrial tools such as ABAQUS or NASTRAN [2] or develop home made tools. Another alternative is to use high level software for multiphysics such as COMSOL [3]. The latter permits the developer to significantly speed developments. It shows that it is possible today to design high level tools for the development of complex finite element formulations. But some limits appear in such tools either in the algorithmic aspects or in the finite element formulations [3]. Until now no particular attention has been paid to software architecture dedicated to this kind of problem. Engineers and scientists usually consider that classical object-oriented techniques are efficient enough to deal with their finite element models. In this paper, we aim at drawing the main lines of the design of modern computational tools for the solution of complex multi-fields engineering problems. After a brief review of several approaches to designing modern finite element tools, we propose the basis of a general purpose tool for coupled multi-fields in a multiphysics context. First, the approach is based on software developments closely related to the mathematical algorithms (see [4]). Two new principles based on advanced O.O programming properties are introduced: the local-global consistency principle and the algorithmic consistency principle (see Eyheramendy [7] for a fuller description). These two principles aim at enhancing the structure of finite element codes in the context of multiphysics and more generally in the context of complex formulations. The approach is held in Java. This approach is embedded in the more general context of modern computational mechanics tools [5,6]. The approach is illustrated by examples of the finite element applied to mechanics of porous media: a hydro-mechanics problem.

[1]

R.W. Lewis and B.A. Schrefler, "The finite element method in the Static and Dynamic Deformation and Consolidation of Porous Media", Ed. Wiley, 2000.

[2]

P. Chassagne, E. Vidal-Sallé, D. Eyheramendy and J-F. Jullien, "Mechanical consequences induced by heat and mass transfers during wood drying process", 3rd International Conference on Thermal Process Modelling and Simulation, Budapest, Hungary, 26-28 April 2006.

[3]

W. Habchi, I. Demirci, D. Eyheramendy, G. Morales-Espejel and P. Vergne, "A Finite Element Approach of Thin Film Lubrication in Circular EHD Contacts", J. of Trib., In Press, 2006.

[4]

D. Eyheramendy, "Advanced object models for mathematical consistency enforcement in scientific computing", WSEAS Transactions on Mathematics, 4(4), 457-463, 2005.

[5]

D. Eyheramendy, "High abstraction level frameworks for the next decade in computational mechanics", in "Innovation in Engineering Computational Technology", Chapter 3, Eds. B.H.V. Topping, G. Montero and R. Montenegro, Saxe-Coburg Publications, Stirlingshire, UK, 41-61, 2006.

[6]

D. Eyheramendy, "Towards global computational frameworks for multi-physics", 7th World Congress on Computational Mechanics, Los Angeles, USA, 2006.

[7]

D. Eyheramendy and F. Oudin-Dardun, "Object-Oriented Finite Elements Programming in JAVA: Objectives and Basic Principles", Submitted, 2007.

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