[CIG-LONG] Scaling from SI values

[Laetitia Le Pourhiet]

thermal diffusivity  K or Kappa for rocks is 1e-6 m^2s-1
I think you mismatched with thermal conductivity k (as in Fourier law)
which is around 2-3 SI
Kappa = k/rho/cp  (density and thermal capacity )
you should not follow the manual ... for scaling time, it is good to have
viscosity close to 1 but your timescale should be close to the
characteristic timescale of what you actually want to model...  ie. 1e13-15
but not 22...

I described some scaling that works well for long term geology application
in my paper at G3
look at table 2 in
http://www.researchgate.net/publication/235005010_Kinematic_interpretation_of_the_3D_shapes_of_metamorphic_core_complexes/file/79e41510410cb3a769.pdf

hope it helps
Laetitia



On Thu, Aug 8, 2013 at 1:52 PM, Matthias Schmiddunser <
matthias.schmiddunser at uni-tuebingen.de> wrote:

> Hi all,
>
> I have a problem concerning the correct scaling of values for the use in
> Gale. Is there a "recipe" on how to scale the values, starting from known
> SI units?
>
> I want to model compression with temperature-dependent viscosity. The
> viscosity is in the order of 10^22, so I scaled time as s -> 10^22 s and
> mass as kg -> 10^44 kg, as described in the manual. For the thermal
> diffusivity this means a value of 1 W/K*m becomes 10^22. However, in my
> model I get a weird layered temperature structure, with values oscillating
> between the values I set for the bottom and the top once per cell (see
> attached picture). I assume this is due to the too high value of
> diffusivity, but maybe I'm misunderstanding something basic. Any help would
> be deeply appreciated!
>
> Thank you very much,
>
> Matthias
>
> --
> Matthias Schmiddunser
> Department of Geosciences
> University of Tübingen
> Wilhelmstrasse 56
> D-72074 Tübingen
>
> E-Mail: matthias.schmiddunser at uni-**tuebingen.de<matthias.schmiddunser at uni-tuebingen.de>
> Telephone: +49(7071)29-73157
>
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-- 
Laetitia Le Pourhiet
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