1. Reference problem#

1.1. Geometry#

Consider a rectangle of length \(325m\) and width \(10m\) in plane \((\mathrm{0,}X,Y)\).

_images/1000000000000375000000DF5ECDBD3794327099.png

The thickness of the membrane is entered in AFFE_CARA_ELEM via the keyword EPAIS and is equal to \(e={\mathrm{2,2783.10}}^{-5}m\). This thickness is chosen so as to obtain a mass equal to that used in test case SSNL114, at an identical density.

1.2. Material properties#

The material is hyperelastic, almost incompressible, isotropic, whose properties are:

  • \(E=57000\mathit{MPa}\)

  • \(\mathrm{\nu }=0.49\)

  • \(\mathrm{\rho }=2\mathrm{844,23}\mathit{kg}/{m}^{3}\)

We use Saint Venant Kirchhoff’s law of behavior.

1.3. Boundary conditions and loads#

On edges \(\mathit{AB}\) and \(\mathit{CD}\): \(\mathit{DX}=0\), \(\mathit{DZ}=0\).

On edge \(\mathit{AD}\): \(\mathit{DY}=0\).

Gravity is applied to the entire model, it is worth \(g=\mathrm{9,81}m/{s}^{2}\) and is oriented according to (0,0, -1) in the \((X,Y,Z)\) coordinate system.

The non-following pressure is applied to the entire model, it is worth \(p\text{}=\text{}\mathrm{\rho }\ast e\ast g\text{}\approx \text{}\mathrm{0,6357}\mathit{Pa}\) and is oriented according to \((\mathrm{0,0,}-1)\) in the coordinate system \((X,Y,Z)\).

The two loads are treated separately.

1.4. Initial conditions#

An initial voltage of \(10\mathit{MPa}\) is entered in AFFE_CARA_ELEM using the N_ INIT keyword. This tension disappears after the first Newton increment.