[aspect-devel] Rheology and boundary conditions

[Wolfgang Bangerth]

Lev,

> 1. Is brittle rheology implemented in ASPECT?

I don't know -- I suppose it depends on how you parameterize the rheology. 
ASPECT has a few material models that are part of the distribution and I would 
suggest you take a look at the
   Material model
     Model name
variable in the manual that is used to describe the rheology you want to work 
with. The description lists the existing material models and gives an overview 
of what kind of material they describe.

In the end, what we do in ASPECT is that we define the viscosity in terms of 
pressure, temperature, strain rate, and a number of auxiliary variables that 
we call "compositional fields" that one can think of as chemical compositions, 
but that can also be used to track other quantities -- e.g., damage variables 
in damage models. If your rheology can be described in these terms, then it 
can be implemented in ASPECT with relatively little effort. Take a look at the 
section in the manual that describes implementing material models, as well as 
the existing models.


> 2. Are pressure boundary conditions (i.e. only the lithostatic pressure is
> prescribed allowing in- and outflow) or periodic b.c. (the model domain is
> looped in one of the directions) implemented? I asked about the pressure b.c.
> at GeoMod2014 and I was told that I should take a look at one of the branches
> on GitHub, but time has passed since then and I was hoping you could update me
> on this.

Finishing pressure b.c. has been on my list for far too long a time already 
:-( I need to get back to that, for sure before the hackathon in May. Periodic 
b.c. are implemented -- see the manual.

Best
  W.

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