Draft: Added Compressible Stress Case to MaxwellSlipBC

Description

Closed due to broken commit history after rebase. New Merge Request: !75 (merged)

Added compressibleStress formulation of the MaxwellSlipBC to the linFlowPDE.

IncompressibleStress Formulation:

\pmb{\Pi} = \mu_{\mathrm{eff}} [\nabla \mathbf{u} + (\nabla \mathbf{u})^\mathrm{T}]

CompressibleStress Formulation:

\pmb{\Pi} = \mu_{\mathrm{eff}} [\nabla \mathbf{u} + (\nabla \mathbf{u})^\mathrm{T}]+( \lambda- \frac{2}{3} \mu_{\mathrm{eff}} ) (\nabla \cdot \mathbf{u})\mathbf{I}

XML Usage Example: <MaxwellFirstOrderSlip meanFreePath="68e-9" C1="1.1466" formulation="compressibleStress"/>

Merge with: Testsuite!35 (merged)

Check before assigning to a maintainer for review

• the history is clean
• code is well documented and understandable
• there is a testcase (in case of new functionality)
• every commit passes the pipeline

Maintainer checks before merge

• Review is approved, and all comments are resolved
• Check for Testsuite changes, if yes check
  • Testsuite merge request merges fast-forward
  • Testsuite-submodule SHA of every CFS commit references a commit in Testsuite Merge Request
  • Testsuite-submodule SHA of last CFS commit points to HEAD of corresponding Testsuite branch
• Pipeline passes for every commit
  • all tests of the stage test pass
  • tests in the stage test_extra run
  • new tests are actually running (e.g. check if they appear on CDash)