# Altair Radioss 2022.2 Release Notes

## Highlights

• Major improvements for the 2D seatbelt material and slipring
• Continuous development to support the reading of more LS-DYNA keywords and options
• Improvement of solver performance for linear tetrahedron elements and contact interface sorting

## New Features

FVMBAG
• /DT/FVMBAG/2: New timestep formulation and control for the FVMBAG1 and FVMBAG2.
Materials and failure models
• /FAIL/TAB2: New failure model fully compatible with LS-DYNA feature *MAT_ADD_DAMAGE_GISSMO.
• /MAT/LAW120 (TAPO): New connection material to model toughened adhesive polymer.
• New LS-DYNA format reading capability
• *ELEMENT_SEATBELT (only for 1D elements)
• *MAT_063
• *MAT_077_H
• *MAT_B01 (SEATBELT) (1D seatbelt material)
• *SECTION_SEATBELT (only for 1D elements)
Results output and time history
• /H3D/SHELL/NL_EPSP, /ANIM/SHEL/NL_EPSP, /H3D/SOLID/NL_EPSP and /ANIM/BRIC/NL_EPSP: new output for non-local plastic strain
• /H3D/SHELL/NL_EPSD, /ANIM/SHEL/NL_EPSD, /H3D/SOLID/NL_EPSD and /ANIM/BRIC/NL_EPSD: new output for non-local plastic strain rate
• /H3D/SHELL/VONM/TMAX and /H3D/SOLID/VONM/TMAX: new output for the maximum value of von Mises stress over time
• /H3D/SHELL/SIGEQ/TMAX and /H3D/SOLID/SIGEQ/TMAX: new output for the maximum value of equivalent stress over time
• /H3D/SHELL/ENER/TMAX and /H3D/SOLID/ENER/TMAX: new output for the maximum value of specific energy over time
• /H3D/SHELL/DAMA/TMAX and /H3D/SOLID/DAMA/TMAX: new output for the maximum value of damage over time and integration points
• /H3D/NODA/DIS/TMAX: new output for the maximum displacement resultant over time
• /H3D/NODA/VEL/TMAX: new output for the maximum velocity resultant over time
• /H3D/SOLID/TENS/STRESS/TMAX: new output for the stress tensor corresponding to the maximum principal stress (P1) or minimum principal stress (P3) over time and integration points
• /H3D/SOLID/TENS/STRAIN/TMAX: new output for the strain tensor corresponding to the maximum principal strain (P1) or minimum principal strain (P3) over time and integration points
• /H3D/NODA/GPS/TMAX: mean nodal stress tensor corresponding to the maximum principal stress (P1) or minimum principal stress (P3) over time
• /H3D/NODA/GPSTRAIN/TMAX: mean nodal strain tensor corresponding to the maximum principal strain (P1) and minimum principal strain (P3) over time
• /H3D/SHELL/TENS/STRESS/TMAX: new output for the stress tensor corresponding to the maximum principal stress (P1) and minimum principal stress (P3) over time and integration points
• /H3D/SHELL/TENS/STRAIN/TMAX: new output for the strain tensor corresponding to the maximum principal strain (P1) and minimum principal strain (P3) over time and integration points
• /H3D/QUAD/GROUP, /H3D/SHELL/GROUP, /H3D/SOLID/GROUP, /H3D/SPH/GROUP, /H3D/SPRING/GROUP, and /H3D/TRUSS/GROUP: New output to display the element group used in the solver
Other features
• /LOAD/PRESSURE: New pressure load dedicated for hydro-forming where the pressure is applied only in the area not in contact with selected contact interfaces.
• /SENSOR/NIC_NIJ: New sensor based on the Neck Injury Criterion NIJ to stop the computation (/STOP/LSENSOR).
• /SENSOR/TEMP: New sensor activated according maximum, minimum or average temperature of a defined set of nodes.

## Enhancements

Accessing Demo Model Files
You can now click a link, within an Example and Verification Problem, to download the required model file(s).
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.
Transformations
/TRANSFORM: Transformations are now applied in the order written in the model and no longer according to the order of their ID. This change is made to recover Radioss behavior for versions prior to 2021.1. Usually, pre-processing tools write transformations in the same order as their identifier. Thus, a different behavior will only be observed for a few models.
2D seatbelt element and material
• New option Ip=24 in the shell property /PROP/TYPE9 to define the orientation of 2D seatbelt elements with material /MAT/LAW119. The transversal direction of the 2D seatbelt can be defined with a local coordinate system or a vector in the shell property.
• New Error message in the Starter and Engine if the nodes defined in a shell slipring element (/SLIPRING/SHELL) are also defined in a rigid body.
• Section force output is available for 2D seatbelt elements (/MAT/LAW119) with the sum of the shell and spring forces.
• New feature in the seatbelt material /MAT/LAW119.
FVMBAG
• The information about the remaining finite volume elements and the merging information are removed from the Engine listing file.
Element and properties
• /TETRA10: automatic setting of Icpre=1,2 to avoid volumetric locking.
• /PROP/TYPE26: Dmax is now activated and Dmin has been added to Radioss 2022 input format. Failure in tension and compression are available.
Materials and failure models
• /MAT/LAW2: New message in the Engine output file when maximum plastic strain defined in the material is reached for a solid element.
• /MAT/LAW33: New, the skeletal behavior (flag Ka=2) before yield is elastic, with perfect plastic behavior in tensile when maximum tensile stress (sigma_cutoff) is reached.
• /MAT/LAW62: New parameter to better model the degree of compressibility.
• /MAT/LAW80:
• Improvement of the shell formulation for the material law /MAT/LAW80. Small changes in the results is expected.
• Phase transformation is now available during heating process.
• /MAT/LAW90: New exponent Alpha for the unloading behavior.
• /NONLOCAL/MAT: LE_MAX parameter is used to automatically adapt the failure criterion parameters using the element size factor function (fct_IDel) and reference element size (El_ref).
• /FAIL/GENE1: Improvement of the volumetric strain computation. The initial element size is taken into account for regularization and mixed mode failure.
ALE and FSI features
• /MAT/LAW51:
• Volumetric viscosity is removed from the input Iform=12 and kinematic viscosity is automatically computed from each submaterial law composing the mixture.
• Improvement of the behavior when FV material and other ALE material from legacy solver are used in the same model.
• Detonation time is computed taking into account initial vol fraction in case of several explosive sub-materials of /MAT/LAW151 and for any ignition option (/DFS/*).
• /DFS/WAV_SHAPER: use several explosive materials with the wave shaper option and multi-fluid material /MAT/LAW151 is now available.
• /INTER/TYPE19: new flag Igap=1 for automatic gap computation for each Lagrangian surface and each Eulerian or ALE brick.
• /EOS/TABULATED: new tabulated equation of state model.
• Improvement of the Error message if there are several /BEGIN cards with different unit systems or versions in the same //SUBMODEL card.
• /MAT/LAW87: Correction of reading for the tabulated input with format 2022.
• /CNODE: Improvement of the information in the Starter listing file for the CNODE which are merged to /NODE or /CNODE or transformed to /NODE (not merged).
• The material *MAT_006 can be applied to beam and truss elements.
• *SECTION_BEAM: ELFORM=4 is now supported (simplified version).
Results output and time history
• /TH/SPRING: New output LENGTH to get the total length of the spring element in time history file (T01).
• /TH/BRIC:
• New output for 3D solid elements to display material velocity, speed of sound & Mach number output.
• New variables NL_PLAS and NL_PLSR (the /NONLOCAL/MAT option).
• /TH/SHEL: new variables NL_PLAS and NL_PLSR (the /NONLOCAL/MAT option).
• 2D solid element /TRIA can be used in the /H3D/ELEM/SCHLIEREN output file.
• The parallelogram rigid wall (/RWALL/PARAL) was rotated 45 degrees from its correct position in the animation files (/ANIM or /H3D).
• /ANIM/DT and /H3D/DT: Error message is printed if Tfreq is not defined in the card.
Other features
• With the option "-hstp_write", all dependent or include files of the model are described in the HTML file .depx.
• /MONVOL/PRES: Improvement of the field description in the Starter output file.
• /INTER/TYPE24: Improvement of the pressfit behavior (INACTI=-1) where the materials in contact have large stiffness difference.
Scalability and speed up
• /TETRA4: Reduction of the CPU cost for linear tetrahedon elements.
• /INTER:
• Improvement of the sorting algorithm to speed up the computation in case of element failure.
• Improvement of contact interface performance for the treatment of eroded element and free nodes (flag Idel).

## Resolved Issues

Element and properties
• /TETRA10: Improvement of the stress distribution for quadratic tetrahedron elements (/TETRA10) with the formulation Itetra10=2.
• /PROP/SH_*: Starter error for orthotropic shell elements with Ishell=4 and N > 1 and isotropic material.
• /PROP/TYPE14 and /PROP/TYPE6: Failure model is working correctly for linear tetrahedron elements (/TETRA4) with the formulation Itetra4=3.
• /PROP/TYPE14:
• Advanced tangent modulus estimation for Hourglass is now automatically activated for the concrete law /MAT/LAW24 (old Ihkt=2). Result may change from previous versions.
• Correction of the output option /OUTP/BRICK/USERS/FULL for linear tetrahedron elements with the formulation Itetra4=1.
• /PROP/FLUID: QA and QB values are reset to the same default values as /PROP/SOLID. Result may change from previous version with specific models.
• /PROP/TYPE20, /PROP/TYPE21, and /PROP/TYPE22: Constant pressure formulation is better selected according to the material used with the thickshell element. The selected value is printed in the Starter output file (Icpre flag). Results can be different from previous version.
• /PROP/TYPE26: Spring element is correctly deactivated with the option /ACTIVE. Forces were remaining after element deactivation.
• /PROP/CONNECT and /PROP/VOID: New Error message if material is not defined for the solid connection element (/PROP/CONNECT). New Error if material is not defined for a /PROP/VOID part.
• /PROP/CONNECT:
• Improvement of the solid element stability during the material failure process. Engine may fail (NaN) for specific models.
• Correction of the animation file outputs (H3D, ANIM) if stress tensor was requested for all integration points for connection elements.
• /PLY: Behavior correction for /PROP/PCOMPP.
• /PROP/PCOMPP: Correction of memory allocation issue in Radioss Starter when there are stacks (/STACK) with different numbers of plies (/PLY).
Materials and failure models
• /MAT/LAW2: Default value is corrected for Eps_UTS (Iflag=1). It was not set to 1.0.
• /MAT/LAW10: Improvement of the Error message #829 and information added in the Reference Guide about unclosed yield surface definition.
• /MAT/LAW21: Warning message #829 corrected.
• /MAT/LAW36: Warning #2064 corrected for /MAT/LAW36 (PLAS_TAB).
• /MAT/LAW42: Nodal time step estimation for the quadratic tetra element (/TETRA10) in the Starter in order to better estimate the target time step according to % of added mass value.
• /MAT/LAW51: Improvement of the Non-Reflecting Frontier elements (Iform=6) initialization when initial gravity (/INIGRAV) is applied on the full model.
• /MAT/LAW72:
• Improvement of the failure computation with non-local damage (/NONLOCAL/MAT) for solid elements.
• Improvement of yield stress when initial plastic strain EPS0 is defined.
• /MAT/LAW80:
• Correction of the thermal expansion.
• Improvement of the of local yield calculation convergence for solid elements. The previous algorithm was diverging for specific cases.
• /MAT/LAW102: The output of plastic strain in the animation file and time history file is no longer missing.
• /MAT/LAW109: Improvement of the material law behavior. Time step no longer dropping for specific model.
• /MAT/LAW119:
• Correction of numerical issue with 2D seatbelt material. Radioss Engine no loner fails with specific model.
• Correction of the spring creation for the 2D seatbelt. Spring elements no longer missing for specific model.
• /MAT/LAW151: Memory allocation issue correction if the material is defined in the model and not used for the analysis.
• /MAT/LAW200: Material information is correctly shared for the computation of the global material used in the stack (/PROP/TYPE51 or /STACK).
• /FAIL/TAB1: Damage function identifier (fct_IDd) is reported in the Starter output file and correctly used for solid element.
• /FAIL/HASHIN: Correction of failure material behavior with single precision. The results are no longer incorrect.
• /FAIL/TENSSTRAIN, /FAIL/COCKROFT, and /FAIL/ORTHSTRAIN: Correction of the shear behavior for the failure model. The shear components are taken into account. These corrections may change the results of the existing model for large shear deformation, failure will appear for bigger deformation.
• /EOS: Normal termination of Starter and correct Error message when /EOS cannot get mass density from /MAT.
Contact interfaces
• /INTER/TYPE25:
• Improvement of the memory allocation with the options Irem_i2 and Igap and specific model. Radioss Starter no longer failing.
• Improvement of the edge-to-edge treatment for free edges of shell elements if the shell thickness is larger than the mesh size. Unexpected contact forces were displayed.
• /INTER/TYPE18:
• The Warning message #1826 was printed in the Starter output file even if it was not necessary for some specific models.
• Unexpected Warning message #100217 was printed in the Radioss Starter output file.
• Radioss Starter correction when a group of bricks is defined. Radioss Starter no longer failing for specific models.
Results output and time history
• /H3D/*/TENS/STRESS: Correction for the output of the viscous stress. Only the value of first IP is added to the global value of stress.
• /H3D/ELEM/SCHLIEREN: Correction of Engine behavior when this output is requested for model with /SHELL and /SH3N elements.
• /ANIM/SHELL/SIGEQ and /H3D/SHELL/SIGEQ: Correction of the SIGEQ output when there are several integration points through the thickness.
• /TH/BRIC:
• Correction of the strain output for each integration point of the thick shell elements.
• Local stress (LOCSTRS) or local strain (LOCSTRN) output in time history file is now output in the local coordinate system for specific solid property set.
• /TH, /ANIM, and /H3D: Strain tensor for output is now constant after element deletion or deactivation for solid elements and some materials (< LAW28).
• /TH/MONV: Radioss Starter no longer failing where a non-existing monitored volume identifier was defined in the time history card.
• *CONSTRAINED_RIGID_BODY: Improvement of the rigid body assembling. Some secondary nodes no longer missing with specific model.
• *LOAD_BODY: Reading improvement when SF=0 (default).
• The cards written after *END are now ignored.
Other features
• /BCS/CYCLIC: Correction of boundary condition setting when both cyclic boundary (/BCS/CYCLIC) and imposed displacement (/IMPDISP) are defined with skew.
• /ANALY: Improvement of the Radioss Starter Error message when 3D elements are defined for 2D analysis (/ANALY).
• /SUBDOMAIN: Requested entities defined in a sub-domain are now correctly output in time history file (T01).
• /SURF/DSURF: Improvement of the surface deletion for specific cases when segments were removed from solid parts. Some segments were not correctly removed.
• /SENSOR/ENERGY: Correction of the sensor behavior which was not working as expected.
• /RAD2RAD: /PROP/PCOMPP, /STACK and /PLY can now be used with the multi-domain option.
• /MONVOL/FVMBAG1: Correction for the computation of the average airbag output temperature, pressure, area and volume.
• /LOAD/PFLUID: Correction of the pressure direction if the structure is moving faster than the fluid flow.
• /IMPL/QSTAT/MRIGM: Young's modulus variation is taken into account in spring back analysis for the material laws /MAT/LAW36, /MAT/LAW43, /MAT/LAW57, /MAT/LAW60, /MAT/LAW74, /MAT/LAW78, and /MAT/LAW106.
• /INIMAP2D: Correction of internal Energy and Pressure mapping for explosive phase from /MAT/LAW151 to /MAT/LAW51.
• /INIBRI:
• Correction of model reading issue when the value -1 or -2 for Ismstr, Icpre or Iframe is used in the solid property.
• Improvement of the reading for the initial state card. Too many warning messages were printed and the reading time was too long.
• Correction of reading issue of the initial state data for under-integrated orthotropic thick shell elements (/PROP/TYPE21 with Isolid=15).