Altair Radioss 2022.3 Release Notes

Highlights

  • Re-organization of the sensor (/SENSOR) entities with output in the time history and many corrections.
  • Several LS-DYNA keywords are added in the Radioss Starter.
  • Continuous development for the materials and outputs.
  • Time step of the beam element is improved mainly in case of small beam length. This modification may change the mass added in the model computed with constant nodal time step.

New Features

Materials and Failure Models
  • /FAIL/INIEVO: new failure model with damage Initiation and Evolution behavior until the element deletion.
  • /FAIL/SYAZWAN: new failure model dedicated for forming/stamping application for ductile elastic-plastic material.
Animation and Time History Output
  • /TH/SENSOR: New time history to output sensor status.

Enhancements

Element and Properties
  • BEAM: the third node of the beam element is now optional. In case the third node is not defined, the beam element orientation is defined using the beam direction (element direction X) and global coordinate system to define the element direction Y and Z (like spring /PROP/TYPE13).
  • /PROP/TYPE3, /PROP/TYPE18: time step improvement for beam elements. The bending damping stiffness is also improved.
  • /PROP/TYPE18: default bending damping value is reset to 0.01 by default to improve the beam element stability.
Materials and Failure Models
  • /MAT/LAW24: the computed Ottosen parameter is now printed in the Starter listing file (_0000.out).
  • /MAT/LAW36:
    • The failure/damage defined directly in the material law is now output in the animation file (/ANIM/BRICK/DAMA) or .h3d file (/H3D/SOLID/DAMA).
    • Error message is now printed if the Poisson ratio is greater than 0.5 or less than 0.
  • /MAT/LAW58: improvement of the unloading behavior defined with a curve.
  • /MAT/LAW62:
    • New parameter to better model the degree of compressibility
    • New flag, Form to set the parameters as Long-term (Form=2) or Instantaneous (Form=0, 1).
    • Drucker stability criteria are added in Starter output file to check the material stability.
  • /MAT/LAW88: improvement of the material stability and new unloading behavior.
Starter and Engine Output File
  • New error message if the values in the predefined section (L1, L2) are not correctly defined in the integrated beam property /PROP/TYPE18.
  • Improvement of the message in the Engine output file when the sensor (/SENSOR) is activated or deactivated.
  • Improvement of the Starter error message if the case node group used in the rigid wall (/RWALL) does not exist in the model.
Animation and Time History Output
  • /ANIM/ELEM/TSAIWU, /H3D/ELEM/TSAIWU: Tsai-Wu criterion, used for the yield surface computation in the composite materials /MAT/LAW12, /MAT/LAW14, /MAT/LAW15 and /MAT/LAW25, is now available for shell and solid elements.
  • /H3D/ELEM/DAMINI: new output to visualize the damage initiation for the failure model /FAIL/INIEVO.
  • /H3D/NODA/AROT: rotational nodal acceleration can be output in the native .h3d file.
  • /H3D/NODA/GPS/TMAX/N=I: new option to compute the maximum grid point stress tensor only every I cycles. This option helps to same computation time.
  • /H3D/NODA/GPSTRAIN/TMAX/N=I: new option to compute the maximum grid point strain tensor only every I cycles. This option helps to same computation time.
  • /H3D/NODA/PCONT/TMAX: new output to visualize the maximum nodal contact pressure over time.
  • /H3D/NODA/CONT2/TMAX and TMIN: new outputs to visualize the maximum or minimum tied contact force over time.
  • /H3D/NODA/PCONT2/TMAX and TMIN: new outputs to visualize the maximum or minimum tied contact pressure over time.
  • /TH/BEAM: new output - stress global value per element and stress per integration points.
Contact Interfaces, Loads and Boundary Conditions
  • Tied contact (/INTER/TYPE2) switches automatically to penalty method when secondary node is linked to RBE3 or RBE2.
  • /INTER/TYPE8: new parameters to define tangential and normal force limits with linear evolution along the drawbead length.
  • The contact interface /INTER/TYPE21 is now compatible with the option /THERMAL.
  • /INTER/TYPE24 (Inacti = -1): improvement of the pressfit behavior, if the materials in contact have large stiffness difference.
  • /INIBRI/STRS_FGLO: concrete material /MAT/LAW24 is compatible with initial stress setting.
  • /SENSOR/DIST: the sensor DIST can be deactivated when the distance is lower than the limits and reactivated when the distance is greater than the limits.
  • /LOAD/PBLAST: Correction of the air blast pressure formulation (Refer to the equation in Comment 2 in the Reference Guide).
LS-DYNA Format Reader
  • New supported keywords:
    • *AIRBAG_SHELL_REFERENCE_GEOMETRY
    • *CONTACT_TIEBREAK_NODES_ONLY
    • *CONTACT_TIEBREAK_NODES_TO_SURFACE
    • *CONTACT_TIED_SURFACE_TO_SURFACE
    • *DEFINE_FRICTION
    • *DEFINE_TABLE_2D
    • *ELEMENT_PLOTEL
    • *INCLUDE_TRANSFORM
    • *INITIAL_FOAM_REFERENCE_GEOMETRY
    • *MAT_124 (PLASTICITY_COMPRESSION_TENSION)
    • *MAT_177 (HILL_FOAM)
  • The option MPP is read and ignored during the LS-DYNA format model reading of the *CONTACT cards, due to it not being necessary for Radioss solver.
  • *INITIAL_VELOCITY_GENERATION: the local coordinate system is now supported in the initial velocity card.
Time Step and Engine Controls
  • /DT/NODA/CST:
    • The parameter initial_mass_ratio is now used only if its value is greater than 0.
    • The keywords CST1 and CST2 are set as obsolete options.
  • The constant nodal time step takes into account the additional stiffness coming from damping (/DAMP) and the target time step is now kept.
  • The elementary time step of the connection element is now set to 1E+20 so they will be no longer be printed in the smallest element time step table of the output file (_0000.out). Connection elements do not have elementary time step.
Starter and Engine Performance and Scalability Improvements
  • Automatic node and element internal renumbering to save computation time for large models.
  • /SET: Radioss creates internally only the necessary groups, surfaces and edges from the general set. This improvement allows a reduction of the memory used in the Starter phase.
  • Performance improvement in case of multi-threading (SMP or HMPP) for the options /LOAD/PFLUID and /LOAD/PBLAST.

Resolved Issues

Animation and Time History Output
  • /ANIM/ELEM/EPSD: strain rate is always output for the quadratic tetrahedron element /TETRA10.
  • /ANIM/VECT/PCONT2, /H3D/NODA/PCONT2: improvement of the tied contact pressure for solid element.
  • /H3D/ELEM/PEXT: corrections of H3D output for external pressure.
  • /H3D/NODA/SKID_LINE/INTER=i: the skid line was not correctly displayed with specific models since version 2022.
  • /H3D/SOLID/FLDZ/OUTER: differences in FLD zone contour was seen between the Radioss output and the FLD computed by HyperView for thickshell elements.
  • /ANIM/SHELL/FLDF, /ANIM/SHELL/FLDZ: Radioss Engine was failing when /ANIM/SHELL/FLDF or /ANIM/SHELL/FLDZ were defined in specific model.
  • /H3D/SPRING/FORC, /H3D/BEAM/FORC, /H3D/TRUSS/FORC: correction of the 1D element force and moment writing in the .h3d file which was not readable.
Element and Properties
  • /PROP/TYPE9, /PROP/TYPE11, /PROP/TYPE16: correction of the material axis setting with the option IP=23.
  • /PROP/TYPE14 (SOLID): correction of numerical error (NaN) on solid element for specific model.
  • /PROP/SH*: element size regularization is now available for shell formulations Ishell = 1,2,3,4 when nodal time step (/DT/NODA) is used for the computation.
Contact Interfaces
  • /INTER/TYPE2: correction of memory allocation issue for the tied contact /INTER/TYPE2 interface with the flag Ignore=2 or 3.
  • /INTER/TYPE25:
    • Initial penetration reporting was not correct in the Starter output file for contact interface TYPE25 with Inacti=5 (and -1) and specific model.
    • Correction of the temperature computation, due to friction.
    • Contact interface improvement for specific model with single precision version.
    • Improvement of the contact interface with edge-to-edge treatment.
    • Improvement of the option Inacti=5 for single precision version. Some initial penetrations were displayed on specific models.
    • New error message in case option IVIS2=-1 is used on solid components. This option is available only for shell.
  • /FRICTION: correction of memory allocation. Radioss Starter may fail with specific model and configuration.
Materials and Failure Models
  • /EOS/TABULATED: improvement of the EOS behavior for specific input.
  • /FAIL/PUCK: correction of memory allocation. Radioss Starter may fail with specific model and configuration.
  • /FAIL/TENSSTRAIN: correction of the failure message in the Engine file. Time and deformation were reversed in the message.
  • /FAIL/VISUAL: improvement of the displayed value for model with low frequency filter (F-flag=2) and computed with single precision.
  • /MAT/LAW24:
    • Correction of k which is the yield coefficient of the current yield surface.
    • Correction of strain output for /TETRA4 element with Itetra4 = 1 formulation. Strain output was missing.
  • /MAT/LAW25 (Iform=0): correction of the unit for the parameter fmax which is unitless.
  • /MAT/LAW25: correction for memory allocation issue for shell element.
  • /MAT/LAW58:
    • The stress and user variables USR1, USR2 are now output as engineering stress.
    • Correction of the engineering strain output using TH variables USR4/USR5.
  • /MAT/LAW111: model with quadratic tetrahedron element (/TETRA10) no longer fails using single precision version.
  • /MAT/LAW114: improvement of the 1D seatbelt material defined with loading curve and reactivation of seatbelt passing slipring.
  • /MAT/LAW117: incorrect unit was defined for the parameters EXP_B and EXP_BK.
Sensors
  • Improvement of the sensor based on the section force (/SENSOR/SECT) when FX was requested.
  • Correction of the sensor type work (/SENSOR/WORK) behavior when it is defined with rigid body.
  • /SENSOR/ENERGY: correction of the sensor behavior which was not working as expected.
  • /SENSOR/DIST_SURF: sensor DIST_SURF can now be used with any Radioss options where sensor can be defined.
  • /SENSOR/INTER: the sensor was not activated at the right time with contact interface /INTER/TYPE24.
  • /SENSOR/VEL: sensor velocity (/SENSOR/VEL) was not activated in SPMD with specific model.
LS-DYNA Format Reader
  • *CONTACT_TIED: improvement of the parameters SST and MST mapping to Radioss.
  • *INITIAL_VELOCITY_GENERATION:
    • Improvement of the initial velocity setting for the merged rigid bodies.
    • Correction of the initial velocity generation if it is defined in a transformed include (*INCLUDE_TRANSFORM).
  • *MAT_RIGID: local coordinate system was not correctly taken into account in the boundary condition with the flag CMO -1.
  • *MAT_GENERAL_NONLINEAR_1DOF_DISCRETE_BEAM: improvement of the card reading for specific model.
  • *MAT_126 (MODIFIED_HONEYCOMB): improvement of the mapping to the Radioss solid material and properties.
  • *SECTION_BEAM:
    • Rectangular size TS1 and TS2 for CST = 1 are now correctly taken into account for the section definition
    • Correction for the inertia J default value of beam with ELFORM = 2.
  • *SECTION_SOLID: improvement of the solid section reading with ELFORM = 2. It is now read as fully-integrated element Isolid = 18.
  • Correction of the Radioss Starter behavior when importing LS-DYNA format model with multiple includes with common nodes (same ID and same coordinates). Radioss Starter no longer fails with segmentation fault.
Other Features
  • Improvement of the Radioss Starter error message, if the data hierarchy is not correctly defined in the model.
  • Improvement of the Radioss Starter warning message in case of unsupported field in a card.
  • /BCS/CYCLIC: improvement of the boundary condition initialization. Incorrect error message was printed with specific model.
  • /DOMAIN: correction of memory allocation issue in the Radioss Starter.
  • /DT: correction of memory allocation issue for the minimum time step computation.
  • /INIBRI/STRS_F, /INIBRI/STRA_F: the initial states data expressed in the elementary coordinate system were incorrectly rotated if included in //SUBMODEL with /TRANSFORM.
  • /LOAD/PBLAST: removal of an unexpected error message when Exp_data = 3 is setup without a /SURF/PLANE for ground.
  • /MOVE_FUNCT: correction of wrong behavior in case of negative abscissa scale factor for a model with several curves (/FUNCT).
  • /MPC: correction of the Starter listing file. The local ID of coordinate system was reported instead of the user ID.
  • /PARITH/ON: correction of memory allocation issue. Specific model was failing with message #26.
  • /RBE3: correction of Starter initialization for specific models.
  • /TABLE/1: correction of the Starter behavior when there is only 1 point in the table.