1. Reference problem#
1.1. Geometry#

The geometry is a fuel rod with a height \(\mathrm{4,5}m\), a thickness \(\mathrm{0,5}\mathrm{mm}\) and a diameter \(\mathrm{0,9}\mathrm{cm}\), regularly attached, via the support grids, to a guide tube, more rigid, of thickness \(\mathrm{0,5}\mathrm{mm}\) and of diameter \(\mathrm{1,245}\mathrm{cm}\).
1.2. Material properties#
The material is homogeneous, isotropic, and linear elastic. The elastic coefficients are:
\(E=98400\mathrm{MPa}\), \(\nu =0.3\), and \(\rho =6526{\mathrm{kg.m}}^{-3}\) for the guide,
\(E=98400\mathrm{MPa}\), \(\nu =0.3\), and \(\rho =6526{\mathrm{kg.m}}^{-3}\) for the pencil.
1.3. Mechanical modeling#
The grids are DIS_TR stiffness elements, the pencils are POU_D_T Timoshenko elements.
1.4. Boundary conditions and loads#
The pencil is embedded at its ends, and only movements according to \(\mathrm{DX}\) are allowed.