Altair Radioss 2022.1 Release Notes


  • A new version of the Radioss reader is released and the old one is entirely removed. As a consequence, input formats older than V9.0 are no longer supported and there are a few other limitations listed below.
  • The non-local method is extended to all elastic-plastic material and failure models. It can be activated with the new keyword /NONLOCAL/MAT. This option helps to reduce local necking, reducing the mesh dependency (shape and size) to get more accurate and predictive material damage.
  • A new 2D seatbelt slipring and material is available as beta version. There is still some development ongoing to improve the output and the non-linearity in the material.
  • There are also various other developments (material, failure models, contacts, airbags, ...) with continuous improvement of Radioss stability and performance.

New Features

/SENSOR/VEL: new sensor based on node velocity
Materials and failure models
  • /NONLOCAL/MAT: non-local method, initially in /FAIL/GURSON, is extended to all failure models based on plastic strain by adding this new option in the material law
  • /MAT/LAW121: elastic-plastic material with specific strain rate dependency
  • /FAIL/GENE1: failure model for element deletion from maximum pressure, minimum principal strain, equivalent plastic strain, volumetric strain, minimum pressure, maximum principal strain, equivalent stress, shear strain, threshold stress, temperature or time
  • /FAIL/RTCL: failure model based on RTCL formulation
  • /FAIL/SAHRAEI: failure model from MIT for battery material failure
Seatbelt models
  • /MAT/LAW119: material law for 2D seatbelt models (beta version)
  • /SLIPRING/SHELL: slipring for 2D seatbelt models (beta version)
Animation files and time history outputs
  • /H3D/SOLID/THIN: new output option to display average % thinning of thick shell element
  • /H3D/SOLID/THIC: new output option to display average thickness of thick shell element
  • /H3D/SHELL/TENS/BSTRESS: backstress tensors for shell elements can be output in .h3d file for /MAT/LAW36 (1), /MAT/LAW78 (3) and /MAT/LAW87 (1 to 4)
  • /H3D/SOLID/TENS/BSTRESS: backstress tensors for solid elements can be output in .h3d file for /MAT/LAW36 (1) and /MAT/LAW78 (3)
  • /H3D/ELEM/EINTV: H3D output for volumic internal energy for 2D and 3D solid and SPH elements
  • /H3D/ELEM/EINTM: H3D output for massic internal energy for 2D and 3D solid and SPH elements
  • /H3D/ELEM/ENTH: H3D output to display enthalpy in solid and SPH elements
  • /H3D/ELEM/ENTHV: H3D output for volumic enthalpy for solid and SPH elements
  • /H3D/ELEM/ENTHM: H3D output for massic enthalpy for solid and SPH elements
Time step and Engine control
  • /MASS/RESET: new option to reset the mass added in the previous run due to nodal or contact time step treatment at the beginning of the run
  • /DTTSH: new option to have a higher time step (almost the same as a shell's) for thick shells (/PROP/TYPE20, /PROP/TYPE21, /PROP/TYPE22) taking into account only the “in plane” surface


Accessing Tutorial Model Files
You can now click a link, within a tutorial, to download the required model file(s) for that tutorial.
Important: This download option is only available if you (or any user) are connected to the internet. Users attempting to download a model file will be prompted with further directions on how to access the model file online. A zipped package of the model files can be downloaded from the Altair One Marketplace and extracted to a local machine or directory on your company’s local server.
/LOAD/PBLAST: new Abaqus with ground reflection and Mach front
Initial conditions
/INIVOL: improvement of the messages printed in the Starter listing file
/MONVOL/FVMBAG1 and /MONVOL/FVMBAG2: finite volume generation has been improved to reduce the amount of initial finite volumes and get faster computation
Element and properties
/PROP/SOLID, /PROP/SOL_ORTH: the formulation Itetra4=3 for linear tetrahedron (/TETRA4) is generalized and can be used for many material laws
Materials and failure models
  • /MAT/LAW24:
    • strain rate value is output in the animation A-files and H3D files
    • variable yield scale factor from failure surface k is output with the variable VK in the time history
  • /MAT/LAW34: material compatible with shell (/SHELL and /SH3N) elements, beam elements (/BEAM) and truss elements (/TRUSS)
  • /MAT/LAW51: the viscosity is now computed for each sub-material in the ALE cell
  • /MAT/LAW70: stability improvement of the foam material with Isolid=18 and Isolid=24
  • /MAT/LAW76: new error message is printed in case the stress value defined in the yield tables/curves is smaller or equal to 0
  • /MAT/LAW80: now compatible with /THERMAL option in order to speed up the thermal behavior for a given mechanical time frame
  • /MAT/LAW112 (PAPER): new error message in case table or function is missing in the material definition with Itab = 1
  • /MAT/LAW116: improvement of the shear failure for specific models. The failure was not at the right deformation or energy
  • /FAIL/TAB1: new error message in case mandatory table1_ID is not defined
Contact interfaces
  • /INTER/SUB: new feature to sum the contact forces for a part from all contact interfaces in the model, or between 2 sets of parts or elements coming from all contact interfaces defined in the model
  • /INTER/TYPE24: improvement of the pressfit behavior (Inacti= -1) in case materials in contact have a large stiffness difference
  • /INTER/TYPE25:
    • new option Inacti= -1 to model the pressfit behavior between 2 solid components. Initial intersection is removed smoothly from the beginning of the contact activation time.
    • improvement of the Irem_i2 flag behavior when the edge-to-edge option is activated. Non-expected force was displayed.
Other Starter keywords and messages
  • /MERGE/NODE: new option to merge nodes with the same coordinates (within a defined tolerance). The merging can be done for nodes defined in a set or nodes from a set to the other nodes of the model
  • Isolid value in the “PART ELEMENT/MATERIAL PARAMETER REVIEW” of the Starter listing file refers to the one used for the 8 node solid elements even there is another type of solid element in the same part.
LS-DYNA format reader
  • *MAT_NULL: this material can be used for beam and truss elements
  • *MAT_PIECEWISE_LINEAR_PLASTICITY: improvement of the mapping of the flag VP in the materials /MAT/LAW36 and /MAT/LAW44
  • *DATABASE_EXTENT_BINARY: animation files are now Gzipped only in the case DCOMP > 1
  • *ELEMENT_SEATBELT_ACCELEROMETER: mapping information for the added mass, local coordinate system and time history cards was missing in the Starter output file
  • *SECTION_BEAM: predefined sections SECTION_08 and SECTION_11 defined with truss section (ELFORM=3) are now supported
  • *INCLUDE_TRANSFORMATION: Radioss Starter was failing for specific LS-DYNA models with *INCLUDE_TRANSFORMATION cards and transformations
  • Options which are now read:
Time step and Engine control
/IMPL/SOLVER: only PCG and MUMPS implicit solvers are kept, and the other ones are removed. MUMPS solver is now the default solver

Resolved Issues

Initial conditions
  • /INIMAP1D: improvement of the mapping for specific cases. The results were not as expected
  • /INIMAP1D/FILE, /INIMAP2D/FILE: improved error message when /INIMAP1D/FILE or /INIMAP2D/FILE cannot find the given filename
  • /INISHE/THICK: correction of the shell thickness initialization. The initialization was wrong
  • /INISPRI: improvement for the spring types 4, 13, 25 and material /MAT/LAW113 initialization with the option Ilen = 1. The mass and inertia were not correct.
  • /INISHE: correction of shell element initialization issue when damage (/INISHE/FAIL) and yield stress scale factor (/INISHE/SCALE_YLD) are set together on the same part
  • /INIBRI: Radioss Starter was displaying an incorrect error message in case initial state was applied on quadratic tetrahedron elements and Isolid different from 0 or 1
  • /INIBRI/EREF: correction of reading issue for model with /TETRA4, Itetra4=1 and Ismstr=1, 10, 11 or 12
  • /INIBRI/EREF: correction of the element behavior in case positioning (/TRANSFORM) is defined in the model
Other Starter keywords
  • /CNODE
    • improvement of the Starter behavior with the card /CNODE. For some specific models, it was necessary to define the card at least twice in the model to have the correct merging behavior
    • correction of Starter behavior in case the search distance in the /CNODE card is very large. The Starter was failing
    • correction of the merging node behavior. /CNODE was not merged with the correct node for specific cases
  • //SUBMODEL: wrong error message was displayed in case several /BEGIN cards with different input versions were defined in the model. This error message is removed, and the format defined in the first /BEGIN card is used. The other /BEGIN cards in the submodel (//SUBMODEL) are ignored.
  • /SET: qarning message was missing in case a set (/SET) defined inside a set (/SET) did not exist in the model
  • /ADMAS/4: Radioss Starter was failing when void material and property were defined in the added mass type 4
  • /SECT: correction of the numerical issue in the Engine restart when there is SC01 and SC02 files
    • Correction of airbag meshing using HyperMesh mesher (Kmesh=14)
    • Duplicated elements on fabric surfaces are automatically removed from the surface, a warning provides the IDs of the nodes of the elements
    • Improvement of the finite element time step with some modifications in the meshing parameters
  • /MONVOL/AIRBAG1 and MONVOL/COMM1: improvement of the computation of the total mass in uniform pressure airbags in case of multi-component gas. The total value was under-estimated
Materials and failure models
  • /MAT/LAW2: correction of strain rate initialization in case it is not used in the material law
  • /MAT/LAW24: the HBP parameter is now correctly evaluated by Radioss and a warning message is displayed in case of negative values
  • /MAT/LAW35: correction of numerical stability. Radioss computation was failing for specific material definition
  • /MAT/LAW62: improvement of the time step computation for the element with high deformation for better element stability
  • /MAT/LAW90: improvement of the material stability versus strain rate dependency. Model was diverging for some specific cases. Also, result can be very different from previous version.
  • /MAT/LAW78: correction of potential numerical issue (NaN) with Single Precision version
  • /MAT/LAW88: improvement of the material behavior when the flat Tension=1. The unloading behavior was not the expected one
  • /MAT/LAW112 (PAPER): improvement of material stability for specific material definition
  • Improvement of the time step computation for the element with high deformation for better element stability for the hyperelastic materials /MAT/LAW42, /MAT/LAW82, /MAT/LAW92, /MAT/LAW94 and /MAT/LAW95
  • /FAIL/CHANG: correction of the tensile matrix mode equation in the Reference Guide
Element and properties
  • /PROP/TYPE16: airbags with fully-integrated 4-noded mesh was not stable when the element was completely warped
  • /PROP/TYPE6 and /PROP/TYPE14: correction of the strain tensor output for the non-co-rotational formulation (Isolid=1,2,12,17 with Iframe=1). The values were written in the elementary coordinate system, instead of global one as documented
  • /PROP/TYPE17: new error message in case the same ply is used twice in the stack
  • /PROP/SHELL: correction of memory issue with Ish3n=30. Radioss Engine was failing with specific model
Contact interfaces
  • /INTER/TYPE2: improvement of the tied contact force output in the time history and animation file
  • /INTER/TYPE18: behavior improvement with the multi-fluid material /MAT/LAW151. Computation was failing for specific models
  • /INTER/TYPE25:
    • Correction of initial penetration reporting in the Starter output file (_0000.out) with specific model. Non-existing initial penetration was printed
    • Improvement of the contact interface with edge-to-edge treatment for specific cases where some node stays hooked during the computation
    • Improvement of the edge-to-edge treatment for free edge of shell element in case the shell thickness is bigger than mesh size. Unexpected contact forces were displayed
    • Correction of memory allocation issue in the Radioss Starter. Specific model was failing at the beginning of the computation with MPI
  • /INTER/SUB: new error message in case sets are not defined in the /INTER/SUB card
Animation files and time history outputs
  • /TH/NODE: reaction force and moment output improvement for constrained nodes.
  • /ANIM/ELEM/TEMP, /H3D/ELEM/TEMP: temperature was not correctly output for 2D solid element in the animation files. This output is now available when /HEAT/MAT, /ALE/MAT or /EULER/MAT is defined with the material card
  • /TH/QUAD: documentation updated according to the current available variables
  • /CLUSTER: correction of the force and moment time history output defined with local cluster coordinate system
  • /ANIM/BRICK/DAMA: animation files were not readable for the thick shell composite property with more than 9 layers
  • /H3D/SHELL/.../LAYER=ALL: Radioss Engine may stop with segmentation fault for specific model
  • /H3D/ELEM/DENS: improvement of the density output in the .h3d file format. It was different to animation file (A-files) for specific models
  • /ANIM, /H3D: Correction of the rigid wall and section force name in the animation file (A-file and .h3d). The name was not correct for specific models
  • /H3D/NODA/GPS, /ANIM/GPS/STRESS/TENS: correction of the Grid Point Stress value for linear tetrahedron elements (/TETRA4). The results were wrong since version 2021
  • /H3D: in the case of 2D simulation (N2D3D=1 or 2 in the /ANALY card), the deleted elements are now removed from h3d visualization
  • /H3D/SOLID/.../OUTER: skin element generated by the output option /H3D/SOLID/.../OUTER are deleted when the attached solid element is deleted
Seatbelt models
  • /RETRACTOR/SPRING: improvement of the node coordinate check for the spring element inside the retractor. Correction of the sensor ID for the retractor. It was referring to the internal ID and not the user ID
  • /SLIPRING/SPRING: last node of the seatbelt defined in the slipring can not go through the slipring anchorage node
Other input corrections
  • Correction of warning message in case the card format of *MAT_002 was not the expected one
  • Radioss Starter was failing for specific model with *INCLUDE_TRANSFORMATION cards and transformations
  • Failure models were missing during the model reading for several material laws *MAT_...
  • Node in time history output was duplicated when card *DATABASE_BNDOUT was set in the model
  • Reading improvement when *DEFINE_BOX is used in *INITIAL_VELOCITY
  • The materials can now be read with their number (*MAT_024)
Time step and Engine control
  • /DT/THERM: time step was not correctly updated for model with tied contact (/INTER/TYPE2). The computation was diverging with default time step scale factor
  • /STATE/BRICK/FAIL: Engine was failing with segmentation fault for specific model
  • /EIG and /IMPL/BUCKL: correction of memory issue. Engine was failing
  • /IMPL/QSTAT/MRIGM: Young’s modulus variation is now taken into account in the spring back analysis for the material laws /MAT/LAW78, /MAT/LAW43, /MAT/LAW36, /MAT/LAW74, /MAT/LAW106, /MAT/LAW57 and /MAT/LAW60

Removed Options

Older Radioss input versions
Radioss input formats prior to V9.0 are no longer supported. The model needs to be updated to a newer format using HyperWorks.
/INIVEL/AXIS: initial velocity written with Radioss V9.0 format is no longer supported. The model needs to be updated to a newer format using HyperWorks.
/BOX: box written with Radioss V12 format is no longer supported. The model needs to be updated to a newer format using HyperWorks.
Time step and Engine control
  • /DT/GLOB: global time step is set as obsolete option and it is removed from the code.
AcuSolve coupling
  • /IMPL/DYNA/FSI: AcuSolve coupling is no longer available. Error message is printed, if /IMPL/DYNA/FSI card is added in the Engine.