4C version v2026.3.0

What's Changed

Breaking Changes

• Renaming and some input refactoring in viscoelasthyper toolbox by @bgoderbauer in #2005
• Minor rework of MAT_electrode by @c-p-schmidt in #2034
• Remove custom implemented functions from elchsinglemat by @c-p-schmidt in #2042
• Move poroelast to vtk output by @c-p-schmidt in #2057
• Remove custom implemented functions: Part 2 by @c-p-schmidt in #2061
• Move heatflux and tempgrad to vtk output by @engstlerL in #2062
• Remove custom implemented functions: Part 3 by @c-p-schmidt in #2064
• Remove thermo trait from thermo solid trait by @rjoussen in #2075
• Remove custom implemented functions: Part 4 by @c-p-schmidt in #2079
• Remove NUMMAT from MIX_Constituent_ElastHyper by @lauraengelhardt in #2080
• Group passive/active material parameters and refactor COMBO muscle model by @lauraengelhardt in #2081

Major changes

• Add performance testing framework by @amgebauer in #1988
• Generate performance report by @amgebauer in #2020
• Collect benchmark test data and generate report by @amgebauer in #2039
• Input: support name-based element block definition by @rjoussen in #1971
• Add kokkosparallel docker and workflow by @PhilipOesterlePekrun in #2162
• Enable using Kokkos with CUDA backend for MIRCO and in general by @PhilipOesterlePekrun in #2012
• Add cmake preset to compile 4C on Darwin by @vryy in #1795

Dependency changes

• Patch Release of Trilinos - 16.2.1 by @jeremylt in #2133

Miscellaneous

• Move scatra input from inpar to scatra by @maxiludwig in #1996
• Improve the error message when using DESIGN ** NEUMANN CONDITIONS: with TYPE: "orthopressure" by @lkoeglmeier in #1999
• Replace raw pointer usage with std::span in Map class by @dharinib98 in #1977
• Remove master/slave in beaminteraction by @davidrudlstorfer in #1998
• Move xfem input from inpar to xfem by @maxiludwig in #1997
• Move s2i input from inpar to scatra by @maxiludwig in #2001
• Add performance test for monolithic solid scatra interaction by @c-p-schmidt in #2004
• Fix reuse of NOX::Nln::Adapter by resetting state by @maxiludwig in #2003
• Node numbering in node set printout when external mesh files are read by @ischeider in #1980
• Slightly increase test tolerance of failing embedded mesh test by @bgoderbauer in #2011
• Fix distance threshold bug ScalarInterp by @dragos-ana in #2010
• [TSI] Fix solver increment handling in partitioned solver by @rjoussen in #2022
• Introduce central manager for viscoelastic states by @bgoderbauer in #2018
• Add temperature derivative evaluation to refJC material by @rjoussen in #2016
• Update tolerance in beam test by @rjoussen in #2026
• [beaminteraction] Assemble penalty contribution into FE matrix by @maxfirmbach in #2028
• Prepare viscoplastic factor for thermo-coupling by @rjoussen in #2015
• Fix 2D solid output of out-of-plane components by @bennoschoenstein in #2027
• Minor rework of ssi solvers by @c-p-schmidt in #2031
• Add more verbose error message to particle code by @ppraegla in #2030
• Add performance result badges to the README by @c-p-schmidt in #2033
• Add Windkessel terminal unit in 1D pipe flow by @engstlerL in #2023
• Clean parallel issues by @georghammerl in #2029
• Add possibility to use functions for bodyforces in porofluid_pressure_based* problems by @lkoeglmeier in #2035
• Introduce non-local growth remodeling by @tuchpaul in #2019
• Minor rework of global_full by @c-p-schmidt in #2038
• [MultSplit Material] Add thermal stress evaluation helper by @rjoussen in #2037
• Add benchmark result badge to the README by @c-p-schmidt in #2043
• Add element timing by @LaSi5002 in #2025
• Enable monitor dbc in monolithic solvers by @rjoussen in #2044
• Enable possibility to use functions for body force contributions in porofluid_pressure_based_elast* framework by @lkoeglmeier in #2040
• Enable inelastic growth in impl-fiber by @tuchpaul in #2052
• Add a completion-oriented schema wrapper by @rjoussen in #2006
• chore: remove old plasticity inpar by @davidrudlstorfer in #2056
• Further infrastructure improvements for viscoelastic materials by @bgoderbauer in #2053
• [Particle] Fix probe for the message with the size tag by @vovannikov in #2058
• Introduce output verbosity levels in reduced lung by @maxiludwig in #2060
• [Particle] Reduce complexity of Particle::PDNeighborPairs::communicate_bond_list() by @vovannikov in #2063
• Rename master/slave to source/target in adapter by @lauraengelhardt in #2055
• Allow vtu mesh import for all beam types in 4C by @isteinbrecher in #2071
• Adapt the workflow schedules by @c-p-schmidt in #2072
• Rename master slave in core by @lauraengelhardt in #2066
• Add thermal effects to the viscoplastic factor by @rjoussen in #2041
• Refactor central infrastructure for viscoelastic materials by @bgoderbauer in #2073
• Monolithic non-local stimulus by @tuchpaul in #2067
• Try fix randomly failing sti test by @c-p-schmidt in #2077
• Implement quasilinear generalized Maxwell model for structural dynamics by @bgoderbauer in #2076
• Futher renaming of master/slave to source/target by @lauraengelhardt in #2078
• Fix build error on lnm cluster thought by @c-p-schmidt in #2085
• feat: beaminteraction -> potential: add potential reduction functions by @davidrudlstorfer in #2088
• Update the lnm cluster presets to actual current capabilities at the cluster bruteforce by @c-p-schmidt in #2087
• Fix sign in 4 ele Maxwell residual by @maxiludwig in #2089
• Clean-up solid materials by @lauraengelhardt in #2090
• Flush error output before MPI abort in main by @rjoussen in #2092
• Preset: Update IMCS cluster preset with vtk by @reginabuehler in #2096
• Further cleanup in preparation for the Adaptive Estimate Interpolation algorithm by @dragos-ana in #2082
• Add thermal effects to the multiplicative split material by @rjoussen in #2083
• Correct invalid names in journal files by @c-p-schmidt in #2086
• Fix circular references in anisotropy framework by @lauraengelhardt in #2094
• Add 3D solid superposition material by @lauraengelhardt in #2095
• Cleanup of scatra ele boundary calc methods by @c-p-schmidt in #2099
• Move inpar_structure to structure_new_input by @maxiludwig in #2103
• Validate output argument contains a prefix by @maxiludwig in #2106
• Rename master/slave to target/source in poro, structure, and TSI modules by @lauraengelhardt in #2101
• Change solver from Superlu to MUMPS for failing beam test by @c-p-schmidt in #2107
• Tensor migration by @tuchpaul in #2084
• Enable vtk based output in red-airways by @lkoeglmeier in #2100
• Fix monitor_dbc DOF iteration in 2D by @bennoschoenstein in #2036
• [Particle] Cache senders and receivers of the refreshed particles by @vovannikov in #2074
• feat: beaminteraction -> potential: add potential reduction distributed endpoint moment compensation by @davidrudlstorfer in #2091
• [beaminteraction]Dual Hermite shapefunctions for Lagrange Multipliers by @dharinib98 in #2009
• Fix get_comm usage in reduced_lung by @rjoussen in #2119
• Fix gmsh node reordering for corner cases by @rjoussen in #2118
• Adaptive endpoint quadrature by @davidrudlstorfer in #2120
• Remove post_output() by @rjoussen in #2125
• Silence Clang-23 Unused Warnings by @jeremylt in #2127
• Refactor the drucker prager model to use tensors instead of matrices by @ischeider in #2007
• [Particle] Do not use ParticleObjShrdPtr for commicating particle data by @vovannikov in #2117
• [beaminteraction] Allow output of energy in beam-to-solid volume mortar simulations by @isteinbrecher in #2135
• [Particle] Make sdata const and return rdata in particle utils by @vovannikov in #2141
• [beaminteraction]Correct dual hermite shapefunctions by @dharinib98 in #2128
• [geometric search] Allow beam bounding volume based on beams surface by @isteinbrecher in #2140
• [beaminteraction] Update beam-solid preconditioner config by @maxfirmbach in #2143
• [beaminteraction] Post filter penalty contribution by @maxfirmbach in #2144
• A hybrid Ogden-type material model with compression-tension asymmetry control by @lauraengelhardt in #2109
• Remove unused code by @rjoussen in #2151
• Update contributing guidelines w.r.t. AI-assisted contributions by @lauraengelhardt in #2156
• Move fluid input by @davidrudlstorfer in #2150
• Find libbacktrace by name, not hardcoded suffix by @georghammerl in #2160
• Update PR template with disclosure of AI assistance by @lauraengelhardt in #2158
• Preparations for fluid output to vtk based by @c-p-schmidt in #2163
• Migrate fluid-hdg output to vtk-based output by @c-p-schmidt in #2164
• Migrate fluid-poro output to vtk-based output by @c-p-schmidt in #2165
• Fix cut kernel comparison by @vryy in #2161
• Move fluid external forces and fluid hdg output by @c-p-schmidt in #2167
• Add dynamic rebalance to structure problems by @LaSi5002 in #2108
• Adapt fluid conditions output by @c-p-schmidt in #2170
• [bugfix] Fix two flaws regarding strain energy output in the hyperelastic framework by @ischeider in #2147
• Reduced lung vtu input by @maxiludwig in #2166
• Add a performance test for reduced-lung by @maxiludwig in #2142
• Particle Writable State Access by @jeremylt in #2171
• Insert Global::Problem at porofluidelast/-scatra algorithm boundary by @bgoderbauer in #2169
• Detect inconsistent fiber entry and throw an error by @ischeider in #2168
• Particle: Clean up THROW vs ASSERT by @jeremylt in #2178
• Particle Use Enum Class by @jeremylt in #2176
• Migrate output of FluidImplicitTimeInt to vtk-based output by @c-p-schmidt in #2172
• Support inhomogenous element blocks (in input only) by @rjoussen in #2123
• Fix cell_block id access in reduced lung by @rjoussen in #2181
• Docker update more robust dependencies hash by @ppraegla in #2175
• Add structured tree terminal unit by @engstlerL in #2180
• Remove redundant definition from input file by @c-p-schmidt in #2185
• [Actions] Temporarily disable kokkoscuda_build workflow due to ccache issue by @PhilipOesterlePekrun in #2186
• [Particle] Improve bin weight estimate by @vovannikov in #2145
• Clean-up 1D pipeflow by @engstlerL in #2195

Contributors

List of all contributors who authored, committed, reviewed, or commented on accepted pull requests for this release.

• Authors / Committers:
  @amgebauer @maxiludwig @bgoderbauer @c-p-schmidt @engstlerL @rjoussen @lauraengelhardt @lkoeglmeier @dharinib98 @davidrudlstorfer @LaSi5002 @jeremylt @dragos-ana @ppraegla @georghammerl @tuchpaul @vovannikov @isteinbrecher @reginabuehler @bennoschoenstein @ischeider @maxfirmbach @PhilipOesterlePekrun @vryy

• Reviewers:
  @davidrudlstorfer @c-p-schmidt @bgoderbauer @ischeider @lkoeglmeier @dragos-ana @rjoussen @maxfirmbach @lauraengelhardt @tuchpaul @mayrmt @isteinbrecher @amgebauer @jeremylt @ppraegla @slfuchs @georghammerl @maxiludwig @engstlerL @vovannikov @mairehenke @knarfnitram @bennoschoenstein @m-frey @dharinib98 @sebproell @PhilipOesterlePekrun

New Contributors

• @LaSi5002 made their first contribution in #2025

Thanks to first-time contributors to 4C!

Full Changelog: v2026.2.0...v2026.3.0