[CIG-SHORT] problems applying initial stress conditions

[Lucas Abraham Willemsen]

Hi,

After completing the Pylith tutorials I tried to model some small problems by adapting the tutorial files. When doing this I ended up with some problems I can not explain.

I wanted to model a fully elastic block cut in half by a rate and state friction fault. The entire block has the name 'elastic'. I try to apply an initial compressional stress of 10 MPA in the x direction. I then impose a y-velocity on both the negative and the positive x faces of the block in order to get a shear stress on the fault. This attempt is given the name 'test5_dynamic.cfg' (please ignore the comments, they are remnants from the 'step14' tutorial).

The biggest problem is that the initial stress of 10 MPa is not applied to the entire block with the name 'elastic'. Instead, it is applied to a strange F-shaped region which is not defined in my cubit scripts (which included in 'mesh' folder). I believe that because of this reason the fault slips uniformly instead of sticking and slipping. A figure of the strange F-shape is included in the archive I attached to this email.

In order to investigate the problem I removed the slip rate on the block while keeping the initial conditions. The name of this experiment is 'test7_dynamic.cfg'. The stress situation at t = 0 still had the weird F-shaped region to which the 10 MPa was applied. In the next time steps this strange F-shaped region did not change shape. Some parts of the block had no stress on them while others (in the F-shape) had 10 MPa. I am puzzled by what is going on. I would be very grateful if someone could show me where I made a mistake.

The file showing the stress situation has the name 'testX-dynamic-stressstrain.xmf' in which X is either a 5 or a 7 depending on which problem is run.

Cheers,
Lucas

P.S.
Paraview does not allow me to investigate the components of the stress tensor for some reason. I can only see one value for 'stress'.

(I could not include the HDF5 output files without making the attachment excessively large)
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