Reference problem
=====================


Geometry
---------

Full sphere:

R

Inner radius :math:`R=0.01m`


Material properties
-----------------------

The material assumed to be linear elastic has the following characteristics:

:math:`E=1.E8\mathrm{Pa}`

:math:`\nu =0.3`

:math:`\rho =10000\mathrm{kg}/{m}^{3}`


Boundary conditions and loads
-------------------------------------

The structure studied is free in space.