[CIG-MC] I need a material model with depth dependent density (only).

[Wolfgang Bangerth]

Gerry,
I think Eh was describing the way this would be done with Citcom. I suppose 
you want to use ASPECT, however, so his approach will not help.

> I need a material model of the form
>
>             \rho_0 + \Delta \rho + \rho_0 \alpha \Delta T    = if z < 0.5 D
>
>     \rho(T) =
>
>             \rho_0 - \Delta \rho + \rho_0 \alpha \Delta T     = if z > 0.5 D
>
> where D is the height of the domain.
>
> but the equation is different when z < 0.5 than when z > 0.5.

You'll need to write your own material model. But the "simpler" model is 
pretty close to this already, so taking this as a starting point (i.e., 
copying that file and renaming the model to whatever you want to call it) 
would likely be fairly trivial.

Best
  Wolfgang

-- 
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Wolfgang Bangerth               email:            bangerth at math.tamu.edu
                                 www: http://www.math.tamu.edu/~bangerth/