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Basic Idea and Motivation

FELYX is an object oriented Finite Element Method (FE/FEM) code written in C++. Further, FELyX is an open source software freely accessible for everyone.

The main motivation to write FELyX was to have a free and object oriented Finite Element code that is numerically efficient and allows to access the Finite Element calculation at any level. Dependence of the optimization, the access to all kind of information is requested. Hence an efficient postproccesing structure is also a main topic.

The need for this arose within PhD thesis in the field of Structural Optimization at the Swiss Federal Institute of Technology Zurich (ETH Zurich) in the group Structures Technology (IMES-ST). As numerical optimization methods Genetic Algorithms are mainly used and sometimes Gradient Methods. This means that we typically have to evaluate thousands of similar Finite Elements Models (therefore efficiency is definitively a point).

Meanwhile FELyX is also used in other fields like LCM calculations or smart structures. FELyX is currently advanced by EVEN AG and the group Structures Technology.

Further information is published here.


Since the start of the project the finite element library was already used for a number of applications, e.g.

  • Implementation of minimum compliance topology optimization methods
  • Liquid Composite Molding (LCM) process simulation
  • Specialized element formulations for composite materials
  • Implementation of new failure criteria for composite materials
  • Implementation of new iterative solver strategies for the special purposes of optimization
  • Realization of mesh-coupling algorithms for our structural-fluid coupling software