What's New

View new features for Radioss 2024.1.

Altair Radioss 2024.1 Release Notes

Highlights

  • Continuous development for the LS-DYNA format reader.
  • Improvement for the shell composite to better take into account the shell offset in the element and also in the contact interface.
  • Many other enhancements in the crash and ALE/FSI analysis features, including material & failure, contacts, SPH and output.
  • Several verification problems have been added to the documentation.

New Features

LS-DYNA Format Reader
New LS-DYNA format reading capability
  • *CONTACT_AIRBAG_SINGLE_SURFACE
  • *DAMPING_RELATIVE
  • *DATABASE_HISTORY_SPH
  • *DEFINE_ELEMENT_DEATH
  • *ELEMENT_SEATBELT_SLIPRING
  • *ELEMENT_SPH
  • *EOS_001 (LINEAR_POLYNOMIAL)
  • *INITIAL_AXIAL_FORCE_BEAM
  • *MAT_001_FLUID (ELASTIC_FLUID)
  • *MAT_138 (COHESIVE_MIXED_MODE)
  • *SECTION_SPH
ALE and FSI options
  • New ALE grid control /ALE/GRID/FLOW-TRACKING which is computed according to the center of mass motion of the ALE domain. This option can be used for bird strike with a bird and the surrounding air modeled in ALE domain.
  • Sliding Wall boundary condition (/BCS/WALL) can block or allow flow normal to a given face for collocated scheme (multi-fluid material, /MAT/LAW151).
  • New simple equation of state function /EOS/EXPONENTIAL to model pressure and time and independent from density and energy.
Elements and Properties
  • More predefined sections have been added in the integrated beam property /PROP/TYPE18.
  • New flag Ioffset in /DEF_SHELL to take into account the shell offset in the contact interfaces (/INTER/TYPE7, 11, 18, 19, 21, 24 and 25) for composite shell elements. New output /H3D/NODA/SHELL_OFFSET to have a better comprehension of contact behaviors when Ioffset=1 is used.
Materials and Failure Models
  • New material law /MAT/LAW126 to describe brittle materials, such as ceramics and glass based on the first Johnson-Holmquist model: JHC
  • New damage output for composite failure modes per material and damage mode.
    • /H3D/ELEM/DAMG/ID=<mat_ID>/MODE=<mode ID>
    • /H3D/ELEM/DAMG/ID=<mat_ID>
    • /H3D/ELEM/DAMG
  • New model /FAIL/FRACTAL_DAMAGE for random walk damage initialization in Starter.
  • New output /H3D/ELEM/FAILURE for the reserve factor and failure index for each listed failure model.
Loadcase, Constraints and Contact Interfaces
  • New option /PRELOAD/AXIAL to set preload axial force for spring beam and truss elements.
Engine file options
  • New option /ADYREL/1 to apply automatic dynamic relaxation on a set of nodes.

Enhancements

LS-DYNA Format Reader
  • New flags SOFT=-7 (node to surface), -11 (edge to edge) or -19 (surface to surface with edge treatment) in *CONTACT_AUTOMATIC_GENERAL to get contact with nonlinear stiffness.
  • New flag SOFT=-7 in *CONTACT_ERODING_SINGLE_SURFACE to use contact interface with nonlinear stiffness.
  • Initial and maximum time step from LCTM in *CONTROL_TIMESTEP is used for the time step (using /DTIX).
  • Keyword *DATABASE_HISTORY_{OPTION}_SET is now read for all input types.
  • Reading improvement for the lower plastic strain value EFMIN in *MAT_015.
  • Reading improvement in case H > 0 but unloading curve LCU is not specified for *MAT_121.
  • The element formulation ELFORM=3 from *SECTION_SOLID is now interpreted as fully integrated solid element (Isolid=18).
ALE and FSI options
  • New error message in case of several /ALE/GRID definitions. Only one grid control is used.
  • The default grid control formulation is changed from /ALE/GRID/DONEA to /ALE/GRID/DISP to get better stability. Small differences in the results are expected from the previous results for models where grid control formulation is not explicitly defined.
  • Nodal speed of sound can now be output for the ALE/EULER components with the keyword /H3D/NODA/SSP.
  • The default value for minimum pressure (Pmin) in /LOAD/PBLAST changes from 1E-20 to 0.0 and lower bound for decay parameter, b of the modified Friedlander model (Imodel=2) is set to 0.0.
Elements and Properties
  • Improvement of the local coordinate definition for the single precision version for beam elements (/BEAM).
  • The distance Z0 is now defined as the position from the meshed surface to the bottom of the stack in shell composite properties /PROP/TYPE17, /PROP/TYPE51, /STACK. This change is done to be consistent with other solvers.
  • Improved SPH numerical accuracy by improving option order=1 and making it compatible with SPMD.
  • Non-local approach /NONLOCAL/MAT is now compatible with degenerated under-integrated bricks (thick shells and solid).
  • Flag IP=26 is added to /PROP/TYPE9, /PROP/TYPE10, /PROP/TYPE11 and /PROP/TYPE16.
Materials and Failure Models
  • New parameter in /FAIL/JOHNSON to define the lower bound strain value for the failure criteria.
  • The function/table FCT_SR can be defined with natural log input for strain rate dependency in failure model /FAIL/TAB2.
  • New input curve for temperature effect applied on the damage table in failure model /FAIL/TAB2. It is used only if temperature effect is not defined in the table (dimension < 3).
  • Materials /MAT/LAW44 and /MAT/LAW109 can be used with Equation of State (/EOS) for solid elements.
  • Computation scalability is no longer dependent on the function size for materials /MAT/LAW50, /MAT/LAW76 and /MAT/LAW90.
  • Improvement for the strain rate input and output in material /MAT/LAW83. The strain rate filtering is activated by default (Fcut = 10000Hz) for the total strain rate filtering (Israte=0).
  • The initial elastic modulus E0 is now updated according to the maximum initial tangent of the input curves in /MAT/LAW90. The maximum elastic modulus is now the minimum value of the maximum curve tangent and 100 times initial elastic modulus E0.
  • New option Tflag curves in /MAT/LAW90 to have linear elastic behavior in tensile using E0.
Loadcase, Constraints and Contact Interfaces
  • The option /TABLE is now compatible with encryption.
  • New gap scale factor Edge_scale_gap to scale gap_min for the edge to edge contact in contact interface /INTER/TYPE19.
  • The option to define contact gap "thick" is now available for spring, beam and truss elements and can be used for contact interface /INTER/TYPE7, /INTER/TYPE11, /INTER/TYPE19, /INTER/TYPE24 and /INTER/TYPE25.
  • New Key=ELLIPS (hyper ellipsoid surface), Key=NODENS (unsortable node set) and Key=PLANE (plane surface) in the general set /SET/GENERAL.
  • Reference metric (/XREF, /EREF) is now compatible with fully-integrated solid elements Isolid=18
Animation and Time History Output
  • New output variable VX, VY and VZ for /TH/PART and /TH/SUBS
Engine file options
  • /INTER: New error message in case Tstart ≥ Tstop.
  • Improvement of the solid element stability (/DT1/BRICK) with specific models with only few elements.
Other features
  • The command line argument -mds_libpath [PATH] is replaced by -mdsdir [PATH].

Resolved Issues

LS-DYNA Format Reader
  • *CONTACT: correction of the mapping for the parameters SST and MST (optional contact thickness).
  • *DATABASE_CROSS_SECTION_PLANE: reading correction of the finite plane size.
  • *DEFINE_TABLE_2D: scale factor SFA was not considered for some specific cases.
  • *MAT_124 (PLASTICITY_COMPRESSION_TENSION): reading improvement in case FAIL=0. The default value was not correctly read.
  • *MAT_224 (TABULATED_JOHNSON_COOK): improvement of the material reading for the failure behavior.
  • *SECTION_BEAM: improvement of the cable section (ELFORM=6) parameter reading in case of material different from *MAT_146.
  • *PART_COMPOSITE: correction of reading error for specific models. Ply ID could be identical to an already existing property ID.
Elements and Properties
  • /DRAPE: correction of memory allocation issue for specific models.
  • /PLY, /PROP/TYPE19: correction of memory allocation issue with specific composite models.
  • /PLY, /PROP/TYPE19: correction of ply information in Starter output file (_0000.out).
  • /PROP/TYPE11: correction of the failure behavior in case of shell offset (Ipos=1) and material law /MAT/LAW25 (Iform=1).
  • /PROP/TYPE13, /MAT/LAW113: correction of the multi-directional failure criterion computation.
  • /RETRACTOR/SPRING: correction of memory allocation issue for SPMD/HMPP version.
  • /SLIPRING: correction of the slipring check in case it is linked to a rigid body which is merged
Materials and Failure Models
  • /EOS: improvement of the sound speed calculation for materials /MAT/LAW44 and /MAT/LAW109.
  • /FAIL/ALTER: default value of Exp_n was not correctly defined to 16.0 as it is documented.
  • /FAIL/ALTER: correction of memory allocation for model with only 3 nodes shell element (/SH3N).
  • /MAT/LAW151: correction for unexpected detonation with specific model.
  • /MAT/LAW51: correction of momentum issue when the option /ALE/SUPG/OFF is used.
  • /MAT/LAW58: correction of animation outputs USR4, USR5.
  • /MAT/LAW87: improvement of the material parameter fitting with tabulated input (Iform=0) and specific models.
  • /MAT/SPR_SEATBELT, /MAT/SH_SEATBELT: correction of the seatbelt check in case an unused material is defined in the model.
Loadcase, Constraints and Contact Interfaces
  • /FUNCT, /TABLE: correction of singularity in logarithmic interpolation routine.
  • /GRNOD/BOX: correction of /BOX/CYLIN reading.
  • /IMPFLUX, /CONVEC: memory allocation correction.
  • /INISH3/STRA_F/GLOB: reading correction for shell elements with global integration (with /MAT/LAW1).
  • /INTER/TYPE2: correction of memory allocation issue with specific models with Spotflag=25 and Spotflag=28.
  • /INTER/TYPE25: correction of warning message when both surfaces are identical.
  • /INTER/TYPE7, /INTER/TYPE19: correction of the flag Irem_gap=2 behavior.
  • /INTER/TYPE7, /INTER/24, /INTER/TYPE25: correction of stiffness computation for Istf > 1 with SPH elements.
Animation and Time History Output
  • /ANIM/ELEM/VFRAC: correction of memory allocation issue for specific models.
  • /H3D/NODA/DMASS, /ANIM/NODA/DMAS: correction of numerical issue for models with tied interface (/INTER/TYPE2) with Spotflag=28.
  • /H3D/NODA/GPS, /H3D/NODA/GPSTRAIN: correction of the output value.
  • /H3D/NODA/PCONT2/TMAX: correction of memory allocation issue. Engine may fail before writing the first animation with specific models.
  • /H3D/SHELL/TENS/STRESS: correction of H3D writing issue for specific models.
Engine file options
  • /IMPL/MUMPS/OUTCORE: option was not printed in the documentation.
  • /STOP/LSENSOR: The stop time was affected by the value defined in /PRINT.
  • /TFILE: Specific model was failing in SPMD in case or force output in different time history files (/ATH, /BTH, etc).

Altair Radioss 2024 Release Notes

Highlights

  • Continuous development for the LS-DYNA format input.
  • Several modifications and improvements for the composite properties with respect to orthotropic angle definition (angle defined in the shell element, flag def_orth removed, new flag values IP=25 and 26).
  • Many other enhancements in the crash and fluid analysis features, including material & failure, contacts, SPH and output.

New Features

Starter Reader
  • New LS-DYNA format reading capability:
    • *CONTACT_ERODING_SURFACE_TO_SURFACE
    • *CONTROL_PARALLEL
    • *DATABASE_GLSTAT_MASS_PROPERTIES
    • *DEFINE_TABLE_3D
    • *ELEMENT_TSHELL
    • *EOS_GRUNEISEN
    • *MAT_030 (SHAPE_MEMORY)
    • *MAT_154 (DESHPANDE_FLECK_FOAM)
    • *MAT_187 (SAMP-1)
    • *MAT_252 (TOUGHENED_ADHESIVE_POLYMER)
    • *SECTION_TSHELL
Animation and Time History Output
  • /H3D/SOLID/TENS/STRAIN/OUTER_AVERAGE: new result output to display outer average strain tensor strain value.
  • /H3D/SHELL/HC_DSSE_Z, /H3D/SHELL/HC_DSSE_F: new output to display the failure zone factor and damage factor indicator.
  • /H3D/ELEM/VECT/ACC: fluid acceleration can be output in .h3d file for cell centroids (/MAT/LAW151).
Materials and Failure Models
  • /FAIL/ORTHENERG: new orthotropic failure criterion based on fracture energy.
Loadcase, Constraints and Contact Interfaces
  • /DAMP/VREL: new Rayleigh damping computed from the average velocity of the node set or rigid body main node motion.
Engine Control File
  • New option to reset the status of all or selected sensors at the beginning of the run.

Enhancements

LS-DYNA Format Reader
  • The option BETA is now supported in *ELEMENT_SHELL.
  • *MAT_058 (LAMINATED_COMPOSITE_FABRIC): reading and mapping improvement.
  • *MAT_071 (CABLE_DISCRETE_BEAM): improvement of the mapping to /MAT/LAW113 with Ileng=1.
  • The material *MAT_074 (ELASTIC_SPRING_DISCRETE_BEAM) is now mapped to /MAT/LAW113 for a more accurate result.
  • *MAT_NULL: reading enhancement for null material reading when *EOS is defined on the solid element part.
  • *SECTION_SHELL: reading improvement for the shell element linked to composite materials.
  • Parallel arithmetic method is turned to off by default for the LS-DYNA format input.
  • The main node of the rigid body coming from *MAT_RIGID is now positioned in the C.O.G of the secondary nodes (only if the position is not explicitly specified).
  • *DEFINE_SD_ORIENTATION: The stiffness direction was not correctly read when the option TITLE is defined.
Elements and Properties
  • /PROP/SPH:
    • The viscosity effect is removed in tension behavior to reduce its effect on the SPH behavior.
    • The viscous parameters qa and qb are renamed to Beta and Alpha to be more consistent with the literature.
  • /PROP/TYPE16: element behavior improvement in case failure model (/FAIL) is linked to the component.
  • The angle defined in the shell element is now added to the orthotropic angle value in any case in the composite property and stack.
  • The flag def_orth defined on the ply (/PROP/TYPE19, /PLY) is removed, phi_s angle on elements is always considered, and used in conjunction with the flag IP on the stack definition. For data in older input versions that used def_orth = 1, the previous versions reference frame behavior can be replaced with the flag IP=26 defined in the composite property or stack.
  • New flag IP=25 to define the first direction of an orthotropic material according to the azimuthal direction of a cylindrical coordinate system.
  • New generic check for the compatibility with material, element, and properties.
Materials and Failure Models
  • /FAIL/BIQUAD:
    • Default value for parameter S-Flag is changed from 1 (no minimum) to 2 (plain strain is global minimum) to avoid numerical issue and wrong failure behavior.
    • New option to create stress softening before element deletion.
    • This failure model can be used for beam elements (/PROP/TYPE3 and /PROP/TYPE18).
  • /FAIL/GENE1: VOLFRAC is no longer active for shell elements.
  • /FAIL/HC_DSSE: new flag Ifail_sh=4 to compute the failure criterion but without element failure or stress reduction.
  • /FAIL/JOHNSON: this failure model can be used for beam elements (/PROP/TYPE3 and /PROP/TYPE18).
  • /FAIL/TAB2: Lode parameter can be used for the mesh dependency scaling with IREG=2.
  • /MAT/LAW11 (BOUND): new error message in case the material is associated with an incompatible material law.
  • /MAT/LAW70: new curve smoothing and de-intersection for tabulated material law. The modified curves are printed in the Starter output file.
  • /MAT/LAW76: improvement of the hardening model.
Loadcase, Constraints and Contact Interfaces
  • /INTER/TYPE24:
    • Improvement of the contact stiffness definition for the pressfit option (Inacti=-1) to better solve the initial penetrations.
    • New option Inacti=-2 is added with high stiffness.
  • /INTER/TYPE25: improvement of the contact behavior. Radioss Engine was hanging in the contact sorting for specific model.
  • /MONVOL/FVMBAG1: the options Kmesh=2 and 4 are removed from Radioss. They are automatically replaced by Kmesh=12 or 14. Differences in the results are expected.
  • New error message in the Starter and Engine in case the nodes defined in the shell slipring element (/SLIPRING/SHELL) are not defined in a rigid body.
Animation and Time History Output
  • /H3D/ELEM/DAMG: the options PLY and LAYER are now available for the coupled damage output.
  • /H3D/ELEM/EINTV: internal energy per volume unit is now available for shell and beam elements.
  • /H3D/ELEM/VECT/CONT: contact reaction forces can be post-treated on the fluid side in .h3d file for the multi-fluid material law /MAT/LAW151 and the FSI contact interface /INTER/TYPE18.
Engine Performances and Scalability
  • Compression library update with Zlib for the option /ANIM/GZIP and /STATE/STR_FILE.
  • Improvement of the computation speed for composite elements /PROP/TYPE51.
  • Improvement of option -licwait behavior for specific setting (HHWU managed licenses).

Resolved Issues

LS-DYNA Format Reader
  • *CONSTRAINED_JOINT_STIFFNESS:
    • Reading improvement for different types of joint combinations.
    • Reading correction in case stiffness is not defined in all non-blocked degree of freedom.
  • *DEFINE_TABLE_2D: improvement of the table and function reading. Table identifier was not correctly defined for specific cases.
  • *ELEMENT_SEATBELT_SLIPRING: reading correction in case the keyword is defined in several includes.
  • *INITIAL_FOAM_REFERENCE_GEOMETRY: improvement of the reading speed for the reference geometry.
  • *INITIAL_STRAIN_SHELL, *INITIAL_STRESS_SHELL_{OPTION}: reading improvement for the elastic material.
  • *MAT_ADD_EROSION: improvement of the failure model mapping.
  • *PART_COMPOSITE: correction for the reading of the parameter NLOC.
  • *SECTION_SEATBELT: correction of the entity reading in case there are several seatbelts under the same keyword.
  • Improvement of the LS-DYNA reader speed in case there is a very large number of sets.
Elements and Properties
  • /DRAPE: correction of memory allocation issue for specific model.
  • /PROP/SHELL: initial state for shell element (INISHE) could not be read for part with elastic material (/MAT/LAW1) without global integration (N=0 in the /PROP/SHELL).
  • /PROP/TYPE14: correction of the density output after the element deletion.
  • /PROP/TYPE17: correction of Starter initialization issue when composite /PROP/TYPE51 or /STACK was defined in the same model.
  • /PROP/TYPE11, /PROP/TYPE17, /PROP/TYPE51, /STACK:
    • Correction of the element behavior with shell offset (Ipos > 0) and specific property where the thickness is bigger than the mesh size.
    • Improvement of the time step estimation for composite shell elements with surface offset (Ipos > 0). The time step was too small.
Materials and Failure Models
  • /EOS: correction of the reader when the Equation of State is encrypted.
  • /FAIL/GENE1:
    • Correction of initialization issue when initial state (INISHE) is defined for shell elements.
    • Behavior improvement in case there are no parameters in the failure model. The failure model is ignored, and a warning message is printed in the Starter output file.
  • /FAIL/TAB1: correction of the failure model reading.
  • /MAT/LAW1: correction of the shell stress and strain tensor output in the animation files for the upper and lower surfaces.
  • /MAT/LAW12: plastic work (/H3D/SOLID/WPLA) and specific energy (/ANIM/ELEM/ENER) are no longer missing in the .h3d output file.
  • /MAT/LAW57: correction of the equivalent stress computation for the output (/ANIM/ELEM/SIGEQ, /H3D/ELEM/SIGEQ).
  • /MAT/LAW58: improvement of the shell behavior with QEPH formulation (Ishell=24).
  • /MAT/LAW95: The stress calculation is corrected for the polynomial hyperelastic energy function. A new flag Iform to fit strain energy density formulation.
  • /MAT/LAW109: correction of the strain rate dependency with failure criteria.
  • /MAT/LAW112: initial state defined in /INIBRI cards were not correctly set in the elements.
Loadcase, Constraints and Contact Interfaces
  • /INTER: correction of the contact surface orientation of the linear tetrahedron element.
  • /INTER/TYPE18: improvement of the contact interface with /MAT/LAW151 and specific model.
  • /INTER/TYPE24: correction of potential issue in the sliding behavior.
  • /INTER/TYPE25: correction of the memory allocation for specific model.
  • /LOAD/PBLAST: warning message for /LOAD/PBLAST is now displayed in correct unit system.
  • /SENSOR/ENERGY: correction of time delay behavior for specific model.
Animation and Time History Output
  • /H3D: correction of output issue for the tensor of the solid element requested on a set of parts.
  • /H3D/QUAD/TENS/DAMA: memory allocation correction for Isolid=17.
  • /H3D/SHELL/PHI/PLY=ALL, /ANIM/SHELL/IDPLY/PHI/ALL: correction of the ply angle display in the .h3d or animation file for specific model with composite shell elements (/PCOMPP/STACK, /PLY).

Deprecated Options

  • Subcycling options are removed from Radioss.
  • FSI contact interface /INTER/TYPE22 is obsolete option.