u3.11.06 Models TUYAU_3M and TUYAU_6M

Summary:

This document describes for models TUYAU_3M and TUYAU_6M:

• the degrees of freedom carried by the finite elements that support modeling,

• the related support meshes,

• the loads supported,

• non-linear possibilities,

• test cases implementing the models.

The models TUYAU_3M and TUYAU_6M correspond to a formulation of linear elements of straight or curved pipes, which rely on Timoshenko beam kinematics for the movements and rotations of the average fiber and on a shell kinematics for the deformations of the cross section (ovalization, warping, swelling). These transverse deformations are broken down into Fourier series. Modeling TUYAU_3M takes into account a maximum of 3 modes, while modeling TUYAU_6M takes into account 6 Fourier modes.

These models can be used for three-dimensional pipe problems in linear or non-linear mechanical analysis and in small displacements.

• 1. Discretization
  • 1.1. Degrees of freedom
  • 1.2. Support mesh for stiffness matrices
• 2. Assignment of characteristics
• 3. Supported loads
• 4. Nonlinear possibilities
  • 4.1. Law of behavior
  • 4.2. Deformations
• 5. Examples of implementation: test cases