Fsisph

[jmpearl]

SPH multimaterial module, here's a quick summary of the contents:

1. SolidFSISPHHydroBase
   • solid hydro for problems with material property discontinuities
   • selectively apply density sum to individual nodelists
   • "consistent diffusion" option applies diffusion to eps and rho through the velocity gradient
   • diffusion options for specific thermal energy and density
   • modified damage implementation (material property reconstruction applied to damage front)
   • currently no RZ or fluidnodelists hydro classes
2. SlideSurfaces
   • slide surface physics package (similar to AV implementation)
   • used to reduce artificial viscosity for slip interface conditions
   • based on interface normals between nodelists
3. compatible energy treatment
   • pairwise thermal energy derivatives used as weights
   • operates on the difference between the conservative and calculated total pairwise work
   • allows pairwise therm energy derivatives to have opposite signs

[jmpearl]

Added Noh and Sod ats tests

[jmikeowen]

This is looking pretty good -- the main thing I'd like to see before we pull is an ATS test that has pass criteria to verify FSISPH is working correctly. Adding test conditions to the Noh/Sod tests is one possibility, but it'd be nice to have one of the test cases that FSISPH was designed for as well.

[jmikeowen]

Looks good -- I'm going to approve and merge this. I did find one testing problem -- the DiametralCompression.py test had an error in the ATS prescription. I fixed that and pushed the change, so we should be OK to go.

[jmikeowen]

This is ready.