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*EXPANSION

Keyword type: model definition, material

This option is used to define the thermal expansion coefficients of a material. They are interpreted as total expansion coefficients with respect to a reference temperature $T_{ref}$, i.e. the thermal strain $\epsilon_{th}$ of a material at a final temperature T and with initial temperature $T_{0}$ is determined by


\begin{displaymath}
\epsilon_{th}=\alpha(T)(T-T_{ref})-\alpha(T_o)(T_o-T_{ref}),
\end{displaymath} (13)

where $\alpha(T)$ is the thermal coefficient at a temperature T. There are two optional parameters TYPE and ZERO. Default for TYPE is TYPE=ISO, other values are TYPE=ORTHO for orthotropic materials and TYPE=ANISO for anisotropic materials. All constants may be temperature dependent. The parameter ZERO is used to determine the reference temperature, default is 0.


First line:

Following line for TYPE=ISO:

Repeat this line if needed to define complete temperature dependence.

Following line for TYPE=ORTHO:

Repeat this line if needed to define complete temperature dependence.

Following line for TYPE=ANISO:

Repeat this line if needed to define complete temperature dependence.

Example:

*EXPANSION,ZERO=273.
12.E-6,373.
20.E-6,573.

tells you that the thermal strain in a body made of this material is $12.^{-6}$ if heated from T=273 to T=373, and $20^{-6}$ if heated from T=273 to T=573.


Example files: beamt, beamt2.


next up previous contents
Next: *FREQUENCY Up: Input deck format Previous: *EQUATION   Contents
Guido Dhondt 2003-08-06