[CIG-LONG] Gale Boundary Conditions & Output

[Rachel Headley]

I'm attempting to model glacial flow which is a nonlinear rheology for a 
tilted block. Right now, I'm using the power law in Gale, but I have  
essentially turned off the temperature component by setting T_0 = 0. I 
have n = 3, and the rest of the components set for a glacier (except all 
variables/constants that are part of the temperature conditions, which I 
have left as defaults since I think they shouldn't matter; eventually, I 
would like to re-incorporate a temperature dependence). I have not 
scaled anything, as it seems to converge without the scaling. I am also 
only running for one time step, as I just want the steady state solution 
without any further deformation. I will be the first to admit that this 
might not be the most elegant way to solve this specific problem.

My velocity boundary conditions are as follows:
Left: vx = 30 m/yr, vy = 0 (set up as a flux boundary, not a moving 
boundary)
Bottom: vx = vy = vz = 0
Top: vy = 0
Back & Front: vz = 0

When I use the specific boundaries, the flow follows how I might expect. 
However, when I set no conditions on Top, Back, and Front, the flow 
shows velocity vectors normal to these boundaries when close to Left and 
mostly negligible at other locations. This behavior surprises me, and 
I'm not sure the best way to work beyond it without setting the boundary 
conditions (Top, Back, and Front) that I have set, which feels a bit 
kloogey to me. Any suggestions for the best way to approach this?

I have a few questions about the boundary conditions.
1) What does it mean if I do not set velocity boundary conditions (i.e. 
for the right side)?
2) Is there a simple way to set the boundaries as a free surface?

I've attached my xml file that I'm using and also a PDF showing the 
comparison between the Gale output and Comsol. I have set up a similar 
problem in Comsol for steady flow, except I'm using an approximation for 
stokes flow (Pattyn, JGR, 2003) to solve for ux and uz, then I use 
conservation of mass to find the vertical velocity (uy). I also have the 
left boundary with an input velocity of 30 m/yr, and all velocities are 
0 at the base. The other sides are free surfaces.

Also, as I'm attempting to do gauge the performance of Gale versus other 
models, I'm interested in the run time and so on. First off, what 
information does the file timeinfo.*.dat hold? Is it run time in seconds 
or something else? Finally, and perhaps this is more from my 
inexperience using the command prompt than anything, but is there a 
simple way to save the verbose output as a text file?

Thanks.
Rachel Headley

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