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Reference Guide
This manual provides a detailed list of all the input keywords and options available in Radioss.
Starter Input
This manual provides a list of all the model definition keywords and options available in Radioss.
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.
ALE and CFD Constraints
Block Format Keyword
/ALE/LINK/VEL
Block Format Keyword With ALE links on grid velocities, given nodes are linked to the given main grid velocities. Either a direction or a combination of directions can be specified.

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Radioss^® is a leading explicit finite element solver for crash and impact simulation.
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This manual provides details on the features, functionality, and simulation methods available in Altair Radioss.
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This manual provides a detailed list of all the input keywords and options available in Radioss.
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  Current Radioss format uses the 12x extension format.
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  New and modified features in Radioss.
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  This manual provides a list of all the model definition keywords and options available in Radioss.
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    Block Format Keyword
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    The Smooth Particle Hydrodynamics method formulation is used to solve the equations of mechanics, when particles are free from a meshing grid.
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    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.
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    Block Format Keyword In Radioss, two node types are available. They use Cartesian coordinate to describe the position of each node.
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    Block Format Keyword
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    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).
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    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.
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    Block Format Keyword
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    Block Format Keyword Monitored volumes can be used to model an airbag, tire, tank, or any closed volume.
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    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.
    - Initial Conditions
      Block Format Keyword
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      Block Format Keyword
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      Block Format Keyword
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      Block Format Keyword
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      Block Format Keyword
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      Block Format Keyword
    - ALE and CFD Constraints
      Block Format Keyword
      - /ALE/BCS
        Block Format Keyword Describes the ALE boundary conditions.
      - /ALE/LINK/VEL
        Block Format Keyword With ALE links on grid velocities, given nodes are linked to the given main grid velocities. Either a direction or a combination of directions can be specified.
    - SPH Constraints
      Block Format Keyword
  - 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.
- 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.
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  This manual contains the description of the keywords for the Radioss Multi-Domain.
- Obsolete Keywords
  Keywords that are still supported, but no longer maintained (*) are considered obsolete.
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- Definition
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This manual presents examples solved using Radioss with regard to common problem types.
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This manual presents solved verification models.
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Theory Manual
This manual provides detailed information about the theory used in the Altair Radioss Solver.
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This manual describes the interface between Altair Radioss and user subroutines.

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/ALE/LINK/VEL

Block Format Keyword With ALE links on grid velocities, given nodes are linked to the given main grid velocities. Either a direction or a combination of directions can be specified.

ale_link_vel — Figure 1.

Format


(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
/ALE/LINK/VEL/`alelink_ID`
`alelink_title`
`node_ID`₁	`node_ID`₂	`grnod_ID`	`grid_dof`	`Iform`
`T`_start		`T`_stop

Definition


Field	Contents	SI Unit Example
`node_ID`₁	First main node number. (Integer, maximum 10 digits)
`node_ID`₂	Second main node number. (Integer, maximum 10 digits)
`grnod_ID`	Node group to which ALE link is applied. (Integer, maximum 10 digits)
`grid_dof`	A combination of X, Y, and Z. =0 Free DOF =1 Fixed DOF (Booleans) (see Codes for Grid Velocity Directions: grid_dof)
`Iform`	Formulation flag. = 0 (linear) $W_{N} = W_{M 1} + (W_{M 2} - W_{M 1}) \frac{1}{N + 1}$ = 1 (maximum) $W_{N} = W_{M 1}$ if $\| W_{M 1} \| > \| W_{M 2} \|$ $W_{N} = W_{M 2}$ if $\| W_{M 1} \| < \| W_{M 2} \|$ = -1 (minimum) $W_{N} = W_{M 1}$ if $\| W_{M 1} \| < \| W_{M 2} \|$ $W_{N} = W_{M 2}$ if $\| W_{M 1} \| > \| W_{M 2} \|$ (Integer)
`T`_start	Start time. (Real)
`T`_stop	Stop time. (Real)

Codes for Grid Velocity Directions: `grid_dof`


(1)-1	(1)-2	(1)-3	(1)-4	(1)-5	(1)-6	(1)-7	(1)-8	(1)-9	(1)-10
			`W`_X	`W`_Y	`W`_Z

Definition


Field	Contents	SI Unit Example
`W`_X	Code for grid velocity in direction X. = 0 Free DOF = 1 Fixed DOF (Boolean)
`W`_Y	Code for grid velocity in direction Y. = 0 Free DOF = 1 Fixed DOF (Boolean)
`W`_Z	Code for grid velocity in direction Z. = 0 Free DOF = 1 Fixed DOF (Boolean)

Comments

ALE links can only be deactivated/activated during Engine computation (/ALE/LINK/ON and /ALE/LINK/OFF).
ALE links can also be added during an Engine run (Engine Input). Radioss will superimpose the grid velocities if different ALE links are defined in both Starter and Engine for the same node.
The grnd_ID input is mandatory.
Formulation 0 needs an unsortable group of nodes (/GRNOD/NODENS).