[CIG-ALL] ASPECT 2.2.0 released

We are pleased to announce the release of ASPECT 2.2.0. ASPECT is the Advanced
Solver for Problems in Earth's ConvecTion. It uses modern numerical methods such
as adaptive mesh refinement, multigrid, and a modular software design to
provide a fast, flexible, and extensible mantle convection solver. ASPECT is
available from


and the release is available from



This release includes the following significant changes:

- New: There is a new matrix-free Stokes solver which uses geometric
This method is significantly faster than the default algebraic multigrid
preconditioner and uses less memory. Free surface and melt transport
are not yet implemented.
(Thomas C. Clevenger, Timo Heister)

- New: There is now a new approximation for the compressible convection
models that is called 'projected density field'.
(Rene Gassmoeller, Juliane Dannberg, Timo Heister, Wolfgang Bangerth)

- Changed: The Geodynamic World Builder has been updated to version 0.3.0.
(Menno Fraters)

- Changed: ASPECT now requires deal.II version 9.0.0 or newer.
(Timo Heister, Rene Gassmoeller)

- New: There is a new, alternative stabilization method for the
advection equation called SUPG.
(Thomas C. Clevenger, Rene Gassmoeller, Timo Heister, Ryan Grove)

- Changed: The entropy viscosity method for stabilizing the advection
equations was substantially improved leading to less artificial diffusion in
particular close to boundaries.
(Rene Gassmoeller)

- New: The 'visco plastic' material model now has an option to simulate
viscoelastic-plastic deformation. The 'viscoelastic plastic' material
model has been superseded and removed.
(John Naliboff, Dan Sandiford)

- New: The "Free surface" functionality has been generalized and is now
part of "Mesh deformation". This change is incompatible to old parameter files
that used the free surface.
(Rene Gassmoeller, Anne Glerum, Derek Neuharth, Marine Lasbleis)

- New benchmarks: entropy equation, viscoelastic cantilever, bouyancy-driven
viscoelastic plate stress, advection in annulus, slab detachment benchmark,
several advection benchmarks, rigid shear, polydiapirs, surface loading.
(Wolfgang Bangerth, Fiona Clerc, Juliane Dannberg, Daniel Douglas, Rene
Gassmoeller, Timo Heister, Garrett Ito, Harsha Lokavarapu, John Naliboff,
Elbridge G. Puckett, Cedric Thieulot)

- Incompatibility: The option to use PETSc for linear algebra has been
removed until further notice.
(Timo Heister)

- New: If the user has the libdap libraries installed then input data can be
pulled from the server instead of a local file.
(Kodi Neumiller, Sarah Stamps, Emmanuel Njinju, James Gallagher)

- New: Implement the "no Advection, single Stokes" and
"single Advection, iterated Newton Stokes" solver schemes.
(Timo Heister, Anne Glerum)

- New: The chunk geometry model can now incorporate initial
topography from an ascii data file.
(Anne Glerum)

- New: The 'depth average' postprocessor now additionally computes the
laterally averaged density of vertical mass flux for each depth slice in the model.
(Rene Gassmoeller)

- Changed: The gravity point values postprocessor has been significantly
(Ludovic Jeanniot, Cedric Thieulot)

- New: There is now a general class
`MaterialModel::Utilities::PhaseFunction` that can be used to model
phase transitions using a smooth phase function.
(Rene Gassmoeller, John Naliboff, Haoyuan Li)

- New: ASPECT now includes a thermodynamically self-consistent compressible
material model, that implements the Modified Tait equation of state
that is described in Holland and Powell, 2011.
(Bob Myhill)

- New: The material models can now outsource the computation of the
viscosity into a separate rheology model.
(Rene Gassmoeller)

- New: ASPECT now includes initial temperature and initial composition
plugins that use ASCII data files to define the initial temperature or composition
at a series of layer boundaries.
(Sophie Coulson, Anne Glerum, Bob Myhill)

- New: Extended spherical shell geometry model to include custom mesh schemes.
(Ludovic Jeanniot, Marie Kajan, Wolfgang Bangerth)

- New: There is a new termination criterion that cancels the model run
when a steady state average temperature is reached.
(Rene Gassmoeller, Juliane Dannberg, Eva Bredow)

- Bug fixes to : parallel hdf5 output, chunk geometry model, initial
topography modules, gplates boundary velocity plugin.
(many authors)

A complete list of changes and their contributing authors can be found at


Wolfgang Bangerth, Juliane Dannberg, Rene Gassmoeller, Timo Heister,
Jacqueline Austermann, Menno Fraters, Anne Glerum, John Naliboff,
and many other contributors.