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Radioss
Radioss

2024.1
Index
  1. Home
  2. Reference Guide

    This manual provides a detailed list of all the input keywords and options available in Radioss.

  3. Starter Input

    This manual provides a list of all the model definition keywords and options available in Radioss.

  4. Materials
  5. Equation of State

    Used by Radioss to compute the hydrodynamic pressure.

  • Welcome
  • What's New

    View new features for Radioss 2024.1.

  • Overview

    Radioss® is a leading explicit finite element solver for crash and impact simulation.

  • Tutorials

    Discover Radioss functionality with interactive tutorials.

  • User Guide

    This manual provides details on the features, functionality, and simulation methods available in Altair Radioss.

  • Reference Guide

    This manual provides a detailed list of all the input keywords and options available in Radioss.

    • File Extensions and Formats

      Current Radioss format uses the 12x extension format.

    • Single File Input

      This format allows running either Starter or Engine with the same file.

    • New Keywords in 2024

      New and modified features in Radioss.

    • Starter Input

      This manual provides a list of all the model definition keywords and options available in Radioss.

      • 2D and 3D Analysis Options
      • Starter Keywords Syntax

        Block Format Keyword

      • Smooth Particle Hydrodynamics (SPH)

        The Smooth Particle Hydrodynamics method formulation is used to solve the equations of mechanics, when particles are free from a meshing grid.

      • Computational Fluid Dynamics (CFD)
      • General Controls

        Block Format Keyword In this group, keywords are used to set default value, global parameter, analysis type, input/output print, damping and ALE and CFD treatment for the whole model. For default value, it is still possible to overwrite in each specific keywords.

      • Nodes

        Block Format Keyword In Radioss, two node types are available. They use Cartesian coordinate to describe the position of each node.

      • Elements

        Block Format Keyword

      • Component and Parts Organization

        Block Format Keyword In this group, keywords are used to combine material and property information (/PART), assemble model (/SUBSET) or define a separate model (//SUBMODEL).

      • Interfaces

        Block Format Keyword Interfaces solve the contact and impact conditions between two parts of a model. Several interface types are available in Radioss and use different contact treatments.

      • Materials
        • Material Compatibility

          Block Format Keyword The following tables list the compatibility options for each of the material laws.

        • Elasto-plastic Materials

          These materials can be used to represent elasto-plastic materials.

        • Hyper and Visco-elastic Materials

          These materials can be used to represent hyper and visco-elastic materials.

        • Composite and Fabric Materials

          These materials can be used to represent composite and fabric materials.

        • Multiscale Materials

        • Concrete and Rock Materials

          In Radioss these materials can be used to represent rock or concrete materials.

        • Honeycomb Materials

          These materials can be used to represent honeycomb materials.

        • Connection Materials

          These materials can be used to represent connection materials.

        • Other Materials

          These materials can be used to represent other materials.

        • Multi-Material, Fluid and Explosive Materials

          These materials can be used to represent multi-material, fluid and explosive materials.

        • ALE and CFD Options

          Block Format Keyword ALE and CFD options used to activate ALE formulation or Eulerian formulation for a given material law.

        • Viscosity Option

        • Leakage Option

        • Thermal Option

        • Equation of State

          Used by Radioss to compute the hydrodynamic pressure.

          • /EOS/COMPACTION

            Block Format Keyword Describes pressure for a porous media such as soil or foam which can be compacted and unloaded.

          • /EOS/EXPONENTIAL

            Block Format Keyword This equation of state provides an exponential time-dependent pressure model. The pressure is defined as P ( t ) = P 0 e α t MathType@MTEF@5@5@+= feaahGart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiuaiaacI cacaWG0bGaaiykaiabg2da9iaadcfadaWgaaWcbaGaaGimaaqabaGc caWGLbWaaWbaaSqabeaacqaHXoqycaWG0baaaaaa@3F99@ .

          • /EOS/GRUNEISEN

            Block Format Keyword Describes the Gruneisen equation of state.

          • /EOS/IDEAL-GAS or /EOS/IDEAL-GAS-VE

            Block Format Keyword Describes the ideal gas equation of state P = ( γ − 1 ) ( 1 + μ ) E MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbbG8FasPYRqj0=yi0dXdbba9pGe9xq=JbbG8A8frFve9 Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeaaeaaakeaaqaaaaaaaaa WdbiaadcfacqGH9aqpdaqadaWdaeaapeGaeq4SdCMaeyOeI0IaaGym aaGaayjkaiaawMcaamaabmaapaqaa8qacaaIXaGaey4kaSIaeqiVd0 gacaGLOaGaayzkaaGaamyraaaa@4316@ .

          • /EOS/IDEAL-GAS-VT

            Block Format Keyword Describes the equation of state for ideal gas (volume - temperature).

          • /EOS/LINEAR

            Block Format Keyword Describes the linear equation of state P ( μ ) = P 0 + B μ MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqGqFfpeea0xe9vq=Jb9 vqpeea0xd9q8qiYRWxGi6xij=hbba9q8aq0=yq=He9q8qiLsFr0=vr 0=vr0db8meaabaqaciGacaGaaeqabaWaaeaaeaaakeaacaWGqbWaae WaaeaacqaH8oqBaiaawIcacaGLPaaacqGH9aqpcaWGqbWaaSbaaSqa aiaaicdaaeqaaOGaey4kaSIaamOqaiabeY7aTbaa@41A6@ with initial pressure and bulk modulus.

          • /EOS/LSZK

            Block Format Keyword Describes the Landau-Stanyukovich-Zeldovich-Kompaneets EOS for detonation products.

          • /EOS/MURNAGHAN

            Block Format Keyword Describes the Murnaghan equation of state.

          • /EOS/NASG

            Block Format Keyword Describes the NASG (Noble-Abel-Stiffened-Gas) equation of state.

          • /EOS/NOBLE-ABEL

            Block Format Keyword Describes the co-volume equation of state P ( v − b ) = R T .

          • /EOS/OSBORNE

            Block Format Keyword Describes the Osborne Equation of State from R.K. Osborne, also called the “quadratic EOS”.

          • /EOS/POLYNOMIAL

            Block Format Keyword Describes the linear polynomial equation of state P ( ρ , E ) .

          • /EOS/PUFF

            Block Format Keyword Describes the linear polynomial equation of state P ( ρ , E ) .

          • /EOS/SESAME

            Block Format Keyword Describes the SESAME table equation of state.

          • /EOS/STIFF-GAS

            Block Format Keyword Describes the ideal gas equation of state for stiffed gas P ( μ , E ) = ( γ − 1 ) ( 1 + μ ) E − γ P * MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbbG8FasPYRqj0=yi0dXdbba9pGe9xq=JbbG8A8frFve9 Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeaaeaaakeaaqaaaaaaaaa WdbiaadcfadaqadaWdaeaapeGaeqiVd0MaaiilaiaadweaaiaawIca caGLPaaacqGH9aqpdaqadaWdaeaapeGaeq4SdCMaeyOeI0IaaGymaa GaayjkaiaawMcaamaabmaapaqaa8qacaaIXaGaey4kaSIaeqiVd0ga caGLOaGaayzkaaGaamyraiabgkHiTiabeo7aNjaadcfadaahaaWcbe qaaiaacQcaaaaaaa@4C31@ .

          • /EOS/TABULATED

            Block Format Keyword Describes the tabulated equation of state P = A ( µ ) + B ( µ ) E MathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbbG8FasPYRqj0=yi0dXdbba9pGe9xq=JbbG8A8frFve9 Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeaaeaaakeaaqaaaaaaaaa WdbiaadcfacqGH9aqpcaWGbbGaaiikaiaadwlacaGGPaGaey4kaSIa amOqaiaacIcacaWG1cGaaiykaiaadweaaaa@40B6@ .

          • /EOS/TILLOTSON

            Block Format Keyword Describes the Tillotson equation of state.

        • Failure Models

          The supported failure models in Radioss.

      • Properties

        Block Format Keyword

      • Monitored Volumes (Airbags)

        Block Format Keyword Monitored volumes can be used to model an airbag, tire, tank, or any closed volume.

      • Constraints

        Block Format Keyword Radioss supports several different kinematic constraints, which are mainly used to impose acceleration, velocity, displacement or temperature in structure or constraint the moving of structure. They are mutually exclusive for each degree-of-freedom (DOF). Two kinematic conditions applied to the same node may be incompatible.

      • Load Cases

        Block Format Keyword In Radioss the following load cases are available. Stress/strain as initial state could be considered by modeling, as well as pressure, gravity, and thermal load.

      • Tools

        Block Format Keyword In this group, tools like transformation, frames, skews, and curve are introduced.

      • Groups(Sets)

        Block Format Keyword Keywords in this group are used to define how to select a group of node, part, elements, lines, or surfaces.

      • Adaptive Meshings

        Block Format Keyword Adaptive Meshing is used in metal forming to divide the element to better describe the geometry. /ADMESH/GLOBAL and /ADMESH/SET are not available for SPMD computation.

      • Output Database

        Block Format Keyword Time histories output for different element groups, section output, or gauge output are described in this group.

      • Obsolete

        Block Format Keyword Keywords that are still supported, but no longer maintained (*) are considered obsolete.

    • Engine Input

      This manual provides a list of all the solution definition keywords and options available in Radioss.

    • LS-DYNA Input

      This manual provides a list of LS-DYNA input files available in Radioss.

    • Optimization Keywords

      Optimization Keyword This manual contains the description of the keywords for the Radioss optimization. This manual is compatible with the version 2018 of Radioss.

    • Multi-Domain

      This manual contains the description of the keywords for the Radioss Multi-Domain.

    • Other Files
    • Definition
  • Example Guide

    This manual presents examples solved using Radioss with regard to common problem types.

  • Verification Problems

    This manual presents solved verification models.

  • Frequently Asked Questions

    This section provides quick responses to typical and frequently asked questions regarding Radioss.

  • Theory Manual

    This manual provides detailed information about the theory used in the Altair Radioss Solver.

  • User Subroutines

    This manual describes the interface between Altair Radioss and user subroutines.

View All Altair HyperWorks Help

Equation of State

Used by Radioss to compute the hydrodynamic pressure.

Compatibility

EOS is used by Radioss to compute the hydrodynamic pressure and is compatible with the material laws:
  • /MAT/LAW3 (HYDPLA)
  • /MAT/LAW4 (HYD_JCOOK)
  • /MAT/LAW6 (HYDRO or HYD_VISC)
  • /MAT/LAW10 (DPRAG1)
  • /MAT/LAW12 (3D_COMP)
  • /MAT/LAW44 (COWPER)
  • /MAT/LAW49 (STEINB)
  • /MAT/LAW102 (DPRAG2)
  • /MAT/LAW103 (HENSEL-SPITTEL)
  • /MAT/LAW109

Supported Keywords

  • /EOS/COMPACTION
    Block Format Keyword Describes pressure for a porous media such as soil or foam which can be compacted and unloaded.
  • /EOS/EXPONENTIAL
    Block Format Keyword This equation of state provides an exponential time-dependent pressure model. The pressure is defined as P ( t ) = P 0 e α t MathType@MTEF@5@5@+= feaahGart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiuaiaacI cacaWG0bGaaiykaiabg2da9iaadcfadaWgaaWcbaGaaGimaaqabaGc caWGLbWaaWbaaSqabeaacqaHXoqycaWG0baaaaaa@3F99@ .
  • /EOS/GRUNEISEN
    Block Format Keyword Describes the Gruneisen equation of state.
  • /EOS/IDEAL-GAS or /EOS/IDEAL-GAS-VE
    Block Format Keyword Describes the ideal gas equation of state P = ( γ − 1 ) ( 1 + μ ) E MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbbG8FasPYRqj0=yi0dXdbba9pGe9xq=JbbG8A8frFve9 Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeaaeaaakeaaqaaaaaaaaa WdbiaadcfacqGH9aqpdaqadaWdaeaapeGaeq4SdCMaeyOeI0IaaGym aaGaayjkaiaawMcaamaabmaapaqaa8qacaaIXaGaey4kaSIaeqiVd0 gacaGLOaGaayzkaaGaamyraaaa@4316@ .
  • /EOS/IDEAL-GAS-VT
    Block Format Keyword Describes the equation of state for ideal gas (volume - temperature).
  • /EOS/LINEAR
    Block Format Keyword Describes the linear equation of state P ( μ ) = P 0 + B μ MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqGqFfpeea0xe9vq=Jb9 vqpeea0xd9q8qiYRWxGi6xij=hbba9q8aq0=yq=He9q8qiLsFr0=vr 0=vr0db8meaabaqaciGacaGaaeqabaWaaeaaeaaakeaacaWGqbWaae WaaeaacqaH8oqBaiaawIcacaGLPaaacqGH9aqpcaWGqbWaaSbaaSqa aiaaicdaaeqaaOGaey4kaSIaamOqaiabeY7aTbaa@41A6@ with initial pressure and bulk modulus.
  • /EOS/LSZK
    Block Format Keyword Describes the Landau-Stanyukovich-Zeldovich-Kompaneets EOS for detonation products.
  • /EOS/MURNAGHAN
    Block Format Keyword Describes the Murnaghan equation of state.
  • /EOS/NASG
    Block Format Keyword Describes the NASG (Noble-Abel-Stiffened-Gas) equation of state.
  • /EOS/NOBLE-ABEL
    Block Format Keyword Describes the co-volume equation of state P ( v − b ) = R T .
  • /EOS/OSBORNE
    Block Format Keyword Describes the Osborne Equation of State from R.K. Osborne, also called the “quadratic EOS”.
  • /EOS/POLYNOMIAL
    Block Format Keyword Describes the linear polynomial equation of state P ( ρ , E ) .
  • /EOS/PUFF
    Block Format Keyword Describes the linear polynomial equation of state P ( ρ , E ) .
  • /EOS/SESAME
    Block Format Keyword Describes the SESAME table equation of state.
  • /EOS/STIFF-GAS
    Block Format Keyword Describes the ideal gas equation of state for stiffed gas P ( μ , E ) = ( γ − 1 ) ( 1 + μ ) E − γ P * MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbbG8FasPYRqj0=yi0dXdbba9pGe9xq=JbbG8A8frFve9 Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeaaeaaakeaaqaaaaaaaaa WdbiaadcfadaqadaWdaeaapeGaeqiVd0MaaiilaiaadweaaiaawIca caGLPaaacqGH9aqpdaqadaWdaeaapeGaeq4SdCMaeyOeI0IaaGymaa GaayjkaiaawMcaamaabmaapaqaa8qacaaIXaGaey4kaSIaeqiVd0ga caGLOaGaayzkaaGaamyraiabgkHiTiabeo7aNjaadcfadaahaaWcbe qaaiaacQcaaaaaaa@4C31@ .
  • /EOS/TABULATED
    Block Format Keyword Describes the tabulated equation of state P = A ( µ ) + B ( µ ) E MathType@MTEF@5@5@+= feaahqart1ev3aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbbG8FasPYRqj0=yi0dXdbba9pGe9xq=JbbG8A8frFve9 Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeaaeaaakeaaqaaaaaaaaa WdbiaadcfacqGH9aqpcaWGbbGaaiikaiaadwlacaGGPaGaey4kaSIa amOqaiaacIcacaWG1cGaaiykaiaadweaaaa@40B6@ .
  • /EOS/TILLOTSON
    Block Format Keyword Describes the Tillotson equation of state.
On this page
  • Compatibility
  • Supported Keywords

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