Altair Radioss 2023 Release Notes


  • Continuous development for the LS-DYNA format input
  • New option to include an LS-DYNA deck in a Radioss one and vice versa
  • Radioss solver is available for computers with ARM processors
  • Many other enhancements in the crash and fluid analysis features

New Features

Starter Reader
New keyword /INCLUDE_LS-DYNA to include an LS-DYNA format deck in Radioss deck.
New keyword *INCLUDE_RADIOSS to include a Radioss deck in an LS-DYNA format deck.
New LS-DYNA format reading capability
  • *MAT_091 (SOFT_TISSUE)
  • *MAT_105 (DAMAGE_2)
  • *MAT_156 (MUSCLE)
Animation and Time History Output
  • /H3D/ELEM/FAILURE/ID=<fail_ID>: new output to visualize the damage in material for each failure model (/FAIL)
  • /TH/SENSOR: new time history output to check sensor(s) status
  • /H3D/ELEM/TILLOTSON, /ANIM/ELEM/TILLOTSON: new contour output for material state in case /EOS/TILLOTSON is used
  • /GAUGE/POINT: new option to define a gauge from a fixed point
  • /H3D/SOLID/VFRAC: new keyword to output all volumetric fractions (VFRAC1, VFRAC2, VFRAC3 and VFRAC4)
  • /H3D/SOLID/FLDF/OUTER_AVERAGE, /H3D/SOLID/FLDZ/OUTER_AVERAGE: new output to display the averaged value of FLD damage factor indicator and FLD failure zone factor, the averaged value from the top and bottom surfaces of the thickshell element
  • /H3D/NODA/CSE_FRICG, /H3D/NODA/CSE_FRIC/INTER=I or ALL: new output to display the contact friction surface energy in the .h3d file
Materials and Failure Models
  • /FAIL/HOFFMAN: new failure model based on Hoffman's theory of composite ply failure
  • /FAIL/MAXSTRAIN: new failure model based on the maximum strain in plane strain dedicated for composite material
  • /FAIL/TSAIHILL: new failure model based on Hill theory of composite ply failure
  • /FAIL/TSAIWU: new failure model based on Tsai-Wu criteria


LS-DYNA Format Reader
  • The units of the entities defined in the include file (*INCLUDE_TRANSFORM) are now transformed with the unit factors defined in the card.
  • *CONSTRAINED_JOINT_STIFFNESS: reading improvement.
  • *MAT_002 (ORTHOTROPIC_ELASTIC): improvement of the reading of orthotropic directions.
    • Improvement of the failure behavior.
    • The Logarithmic scale for strain rate value in the table LCSS is now considered and the option LOG_INTERPOLATION is supported.
    • Improvement of the mapping of the flag VP in materials /MAT/LAW36 and /MAT/LAW44.
  • *MAT_026 (HONEYCOMB): improvement for the reading of the flag AOPT according to latest Radioss capabilities for the material
  • *MAT_034 (FABRIC): the formulation FORM=14 is now read and translated to /MAT/LAW58
  • *MAT_100 (SPOTWELD): option DAMAGE-FAILURE is currently ignored in the spotweld material, and a warning message is printed.
  • *MAT_124 (PLASTICITY_COMPRESSION_TENSION): parameters Ec and RPCT are now read
  • *MAT_126 (MODIFIED_HONEYCOMB): improvement for the reading of the flag AOPT according to the latest Radioss capabilities for the material
Element and Properties
    • New flag Iale to activate ALE and Eulerian formulation for solid elements. This flag is replacing the cards /ALE/MAT and /EULER/MAT.
    • New Starter check to allow only relevant Itetra4 values (0, 1, 3, 1000).
  • New error message if the Ishell flag is not correctly defined in the shell properties.
  • /PROP/TYPE18 (INT_BEAM): improvement of the beam time step. The time step is now higher for specific cases.
  • New element quality criteria are implemented in solid properties to trigger element deletion or switch to SPH.
  • /DRAPE: new option to define slices for each ply with their own orientation.
  • Improvement of the part/material review section in the Starter output file for the quadratic solid element (/BRIC20) defined with Isolid different from 16.
Materials and Failure Models
  • /MAT/LAW36:
    • A new warning message in case curves with different strain rates are intersecting.
    • New option in the flag Fsmooth for logarithmic strain rate interpolation.
  • /MAT/LAW37: this material law is now compatible with 2D analysis.
  • /MAT/LAW51:
    • Formulations Iform=0, 1, 10 and 11 are now obsolete.
    • Formulation Iform=12 is the new default formulation.
    • Viscosity parameters are now automatically calculated from sub-material viscosities.
  • /MAT/LAW66: new optional compression Young's modulus is available.
  • /MAT/LAW88: this material can be used with shell elements.
  • /MAT/LAW76 (SAMP): new warning message in case curves with different strain rates are intersecting.
  • /MAT/LAW79:
    • Strain rate effect is now considered.
    • Strain rate cut off frequency parameter is added.
    • Damage can be post-processed in the animation file and time history file.
  • /MAT/LAW113 (SPR_BEAM): new stiffness scale factor function fct_ID5i for the nonlinear viscous function fct_ID4i.
  • /MAT/LAW119 (SH_SEATBELT): 1D element seatbelts with T connections are now treated as three separate seatbelts. There is no material flow on the T connection node. It is still prohibited to have T connections in seatbelts with slipring and/or retractor.
  • /MAT/120 (TAPO):
    • Improvement of the material formulation to get results closer to physical test.
    • Damage is output in the animation file (/H3D/SOLID/DAMA, /ANIM/BRICK/DAMA).
  • /FAIL/ORTHBIQUAD, /FAIL/BIQUAD: new warning in the Starter output file in case the failure curve becomes negative
  • /MAT/USERij: the curve slope coming from a Table (/TABLE) is now available in the user material library
  • /NONLOCAL/MAT: this option is now compatible with multi-domain approach (/RAD2RAD)
  • Reference density (rho0) is removed from the Equation of State (EOS) and the reference density is used in any case.
Loadcase, Constraints and Contact Interfaces
  • /RBE3: rotational degree of freedom on the dependent node is now automatically activated when an imposed moment is applied on it
  • /ALE/CLOSE is now compatible with /PROP/SOLID
  • /LOAD/PBLAST: new parameter Tstop to stop the pressure load
  • /THERMAL option is now fully-compatible with shell elements
  • /SENSOR/TIME: new stop time option to deactivate the sensor
  • /INTER/TYPE24, /INTER/TYP25: new option to activate contact stiffness based on time step and nodal mass in the contact interface
  • /FRICTION, /INTER/TYPE7, /INTER/TYPE19, /INTER/TYPE21, /INTER/TYPE23, /INTER/TYPE24 and /INTER/TYPE25: new friction model Ifric=4
  • /DT/BRICK/DEL/1, /DT1/BRICK/DEL/1: new element shape criterion in the Engine keyword /DT/BRICK/DEL*/1 and /DT1/BRICK/DEL/1 to delete elements based on solid collapse, maximum aspect ratio, minimum and maximum volume change
Starter and Engine Output
  • More information in the PART review in the Starter output, like property type, material law and framework (ALE, Euler, Lagrangian).
  • Fatal error in cases where a contact interface not compatible with 2D analysis is defined in a 2D analysis model.
  • New warning message in case /FAIL/JOHNSON is used with composite /MAT/LAW25 (where there is no plastic strain, only plastic work).
Animation and Time History Output
  • Strain rate is output for beam and truss elements in the animation file (/ANIM/BEAM/EPSD), in h3d file (/H3D/BEAM/EPSD) and time history file (/TH/BEAM and /TH/TRUSS).
  • /TH/SURF: additional output to display the pressure applied on a surface (/PLOAD, /LOAD/PRESSURE, /LOAD/PBLAST and /LOAD/PFLUID)
  • /TH/INTER: the contact area can be output from contact interface /INTER/TYPE24 and /INTER/TYPE25 or from sub-interface /INTER/SUB. This output gives the area where there is contact force.
  • /TH/SPRING: new flag FAIL to display the maximum failure ratio for the spring element (between 0 and 1)
  • /DYNAIN/DT: new option to zip the DYNAIN file
Engine Performances and Scalability
  • Load balancing improvement for the material /MAT/LAW25, /MAT/LAW82 and for the thickshell elements
  • With the new command line option "-licwait", Radioss Starter and Engine will wait (or sleep) until licenses are available
  • Performance improvement when ALE elements are deactivated or removed from the model
  • /USERWI: Generalization of the option including improved support for SPMD/HMPP

Resolved Issues

LS-DYNA Format Reader
  • *CONSTRAINED_JOINT_STIFFNESS: reading correction for the stiffness.
  • *MAT_034:
    • Shear modulus was not correctly computed
    • Improvement of the AOPT flag reading for material with nonlinear behavior or linear behavior
    • Improvement of the curve mapping for the nonlinear behavior (FORM=+/-14)
Elements and Properties
  • Temperature initialization correction and hourglass control correction for /PENTA6 thick-shell element.
  • Correction of a small error in the mass part computation with shell elements.
  • /STACK: correction of the bending behavior in case a composite stack is offset from the middle surface.
  • Correction of memory allocation issue in case properties /PROP/TYPE22 and /PROP/TYPE6 with sol2sph option are defined in the same model.
  • Filtering is now used for spring failure with IFAIL=0.
Materials and Failure Models
  • /FAIL/ORTHBIQUAD: improvement of the compression and shear response for specific loadcase
  • /FAIL/ORTHSTRAIN: correction of the configuration file for the reader (.cfg). The element size scale function was not correctly read.
  • /FAIL/TENSSTRAIN: the element failure was not correct for the failure model applied on component with preload (/PRELOAD)
  • /MAT/LAW104: improvement of the shell behavior for the formulation Ishell=1, 2, 4
  • /MAT/LAW108: correction of material initialization of Iequi values in case one of hardening parameters H > 0
  • /MAT/LAW120 (TAPO): correction of the Starter output file in case a table is not defined
  • Correction of natural element time-step for specific setting. The initial time step was overestimated.
  • /MAT/USERij: issue correction in user material law with the option GET_VTABLE_VALUE. Radioss Engine was failing
Loadcase, Constraints and Contact Interfaces
  • /ADMAS/1: the added mass and the total mass reported in the Starter output file was not correct for specific model with quadratic tetrahedron elements (/TETRA10).
  • /INIBRI/EREF: improvement of the stress initialization for the solid elements and materials /MAT/LAW92. The stress value was not correct for specific models.
  • /INTER/TYPE*: correction of the orientation of the linear tetrahedron element for the main surface of the contact interface.
  • /INTER/TYPE18:
    • Correction of model reading and decomposition issue with specific model
    • Improvement of the automatic stiffness computation with the option Istf=2
  • /INTER/TYPE24: correction of precision issue in the contact interface treatment for the solid to solid and edge treatment with single precision.
  • /INTER/TYPE25: correction of contact force initialization issue with Inacti=5 for specific model computed with different number of threads (SMP).
  • /LOAD/PBLAST: improvement of the formulation with ground reflection and hemispherical charge (Exp_data=2).
  • Correction of Starter issue when /LOAD/PFLUID and /LOAD/PBLAST are defined in the same input file.
  • /SENSOR/ENERGY: improvement of the sensor behavior to detect constant internal or kinetic energy which are almost null
Animation and Time History Output
  • The position of the recycled SPH (coming out of /SPH/INOUT and reset to the /SPH/RESERVE) was not correct in the .h3d file (/H3D/NODA).
  • *INITIAL_STRAIN_SHELL: the flag LARGE was not written at the right position for three node shell elements
  • Density is now available for shell elements in the animation file (/ANIM/SHELL/DENS, /H3D/SHELL/DENS).
  • /H3D/ELEM/HOURGLASS: output was not available for specific models with shell or solid elements
  • The hourglass output was missing with the keyword /H3D/QUAD/HOURGLASS.
  • /H3D/SHELL/USER/UVAR=ALL/PLY=ALL/IPT=ALL: user variables are now output for the composite property /PROP/TYPE17, /PROP/TYPE51 and /PROP/PCOMPP
  • /H3D/SOLID/FLDZ/OUTER: differences in FLD zone contour were seen between the Radioss output and the FLD computed by HyperView for thickshell elements
  • /TH/PART: correction of part mass output in time history file in case of material failure and element deletion (output issue only)
Starter and Engine Output
  • Improvement of the time step estimation in the Starter output file for elements with ALE formulation.
  • The formulation Isolid=17 defined in /DEF_SOLID was not correctly reported in the Starter output file for 2D analysis.
  • /MONVOL/FVMBAG*: correction in the Starter output file of the vent and porosity names
  • Radioss Starter stops with error message in case material is missing /PROP/TYPE19 ply.
  • /MAT/LAW53: correction of the time step calculation reported in the Starter output file.
  • Radioss Engine was failing when several initial velocity cards (/INIV) were defined in the same Engine file.
  • /RAD2RAD/ON: improvement of the result mapping precision between the domains
  • /TABLE: correction of Starter error when initializing four-dimensional table
    • Correction of the material orientation defined with the vector V for the solid element (/PROP/TYPE6) for model defined inside a //SUBMODEL.
    • The orthotropic angle defined in /PROP/SH_SANDW was not correctly oriented after transformation.
  • Internal scratch files were not using the directory TMPDIR since version 2022.2.