# *DOMAIN DECOMPOSITION

 Define a region for domain decomposition and/or define constraints on the domain decomposition. This option is used to define a domain decomposition region and/or to define constraints on the domain decomposition.
 Related Topics In Other Guides Parallel execution in Abaqus/Explicit

ProductsAbaqus/Explicit

TypeModel data

LevelAssembly

## Optional parameters

DECOMPOSE FACTOR
Set DECOMPOSE FACTOR=N to split the decomposition region into $N*ndomainsUser$ domains, where $nd⁢o⁢m⁢a⁢i⁢n⁢s⁢User$ is the number of domains specified during job submission (the default of $nd⁢o⁢m⁢a⁢i⁢n⁢s⁢User$ is equal to the number of cpus). The default value of N is 1.
DEFINITION

Set DEFINITION=ELSET to specify the domain decomposition region using a user-defined element set.

Set DEFINITION=BOX to specify that Abaqus/Explicit should generate the domain decomposition region consisting of all elements contained within the user-specified box.

ELSET

Set this parameter equal to the name of the element set to define a domain decomposition region if DEFINITION=ELSET. This element set will be split into the user-specified number of parallel domains.

Set this parameter equal to an empty element set if DEFINITION=BOX. The elements will be generated automatically by Abaqus/Explicit.

If this parameter is omitted, this domain decomposition region will include all elements not included in other domain decomposition regions.

METHOD

Set METHOD=RCB (default) to decompose the model via recursive coordinate bisection.

Set METHOD=GRAPH PARTITIONING to decompose the model while minimizing the number of shared nodes.

RCB DIRECTION

Set RCB DIRECTION=XYZ (default) to split the decomposition region into domains using cutting planes normal to the global x-, y-, and z-directions.

Set RCB DIRECTION=X to split the decomposition region into domains using cutting planes normal to the global x-direction.

Set RCB DIRECTION=Y to split the decomposition region into domains using cutting planes normal to the global y-direction.

Set RCB DIRECTION=Z to split the decomposition region into domains using cutting planes normal to the global z-direction.

Set RCB DIRECTION=NOTX to split the decomposition region into domains using cutting planes normal to the global y- and z-directions.

Set RCB DIRECTION=NOTY to split the decomposition region into domains using cutting planes normal to the global x- and z-directions.

Set RCB DIRECTION=NOTZ to split the decomposition region into domains using cutting planes normal to the global x- and y-directions.

## Data lines to define constraints on domain decomposition (when the ELSET parameter is omitted or DEFINITION=ELSET is used)

First line
1. Element set label. This element should be a subset of the domain decomposition region if it is defined by specifying the ELSET parameter.

2. The “words” SAME DOMAIN to specify that all elements in the element set should be constrained to the same domain.

Repeat this data line as often as necessary to define constraints on the domain decomposition.

## Data lines for DEFINITION=BOX

First line
1. X-coordinate of the lower box corner (Xmin).

2. Y-coordinate of the lower box corner (Ymin).

3. Z-coordinate of the lower box corner (Zmin).

4. X-coordinate of the opposite box corner (Xmax).

5. Y-coordinate of the opposite box corner (Ymax).

6. Z-coordinate of the opposite box corner (Zmax).

Second line
1. Element set label. This element should be a subset of the domain decomposition region if it is defined by specifying the ELSET parameter.

2. The “words” SAME DOMAIN to specify that all elements in the element set should be constrained to the same domain.

Repeat this data line as often as necessary to define constraints on the domain decomposition.