LinearThermalExpansibility¶

Type:	2-Tensor, or section
Range:	[v_1, …, v_9]
Default:	-/-
Appearance:	optional

Sets the linear thermal expansion coefficient $\TField{\alpha}^{(\mathrm{L})}$ is the fractional change of length of an infinitesimal small body per degree of temperature change, that is

$\begin{eqnarray*} \TField{\alpha}^{(\mathrm{L})}_{\mathrm{L}} & = & \frac{1}{L} \frac{\dd L}{\dd T}. \end{eqnarray*}$

Units are $\units{1/K}$ . Since the length changes may be anisotropic the thermal expansion coefficient is a rank-2 tensor.

A constant linear thermal expansion coefficient can be defined by assigning a rank-2 tensor:

Material {
  # defines a constant conductivity
  LinearThermalExpansibility =
      [..., ..., ...
       ..., ..., ...
       ..., ..., ...]
}

Assign a scalar for an isotropic thermal expansibility.

For more general cases, the thermal expansibility may be given as a section in order to deal with space, time, and parameter dependent definitions:

# define the density as a section
LinearThermalExpansibility {
  Python {...}
  ...
}

Field definitions within the section LinearThermalExpansibility are summed up. Consult the subsequent sections to see which types of field definitions are allowed.