6 Models

Mostly the concept of model refers to the constitutive equations or complementary laws that are needed to mathematically end up with a well-posed problem. However we need more informations, here, regarding the numerical methods that are used to handle complex problems and geometries. These methods will be implemented in a single file whose basename will identify the code name of the model. The concept of model will then be extended to fit with the set of informations pertaining to:

• The number and kind of equations to be solved
• The complementary laws that are needed to have a well-posed problem
• The informations associated to the numerical methods employed

Models aim at addressing the behavour of the material at the scale of one finite element. Therefore the methods defined in object "Model_t" aim at computing matrix, residual forces, outputs and so on, for the nodes of one element. The object "Element_t" is therefore the main input entry of all methods of object "Model_t".

A short description of the available models can be displayed by typing:

bil -m