MERGE

Contact and tied interfaces
*MERGE
"Optional title"
entype${}_s$, enid${}_s$, entype${}_m$, enid${}_m$, $tol$, mfid, gid, penalty, $\alpha_{max}$
Parameter definition
VariableDescription
entype${}_s$ Slave entity type
options: G, P, PS
enid${}_s$ Slave entity identification number
entype${}_m$ Master entity type
options: G, P, PS
enid${}_m$ Master entity identification number
$tol$ Tolerance for merging (absolute distance)
default: 1% of the master face side length
mfid ID of MERGE_FAILURE command
default: no failure
gid ID of GEOMETRY defining the region to be merged
default: no geometry
penalty Flag to switch to penalty formulation
options:
0 $\rightarrow$ constraint based
1 $\rightarrow$ penalty based
$\alpha_{max}$ Maximum allowed deviation from parallelism
default: $25^\circ$
Description

This command can be used to merge disjointed meshes. Note that the finer element grid should be on the slave side. Interface forces are written to merge.out. Maximum tensile and shear stresses are also output, if a failure criterion has been define (parameter mfid).

Example
Merge disjointed meshes

A flexible pipe with part ID = 10 is merged to a plate with part ID = 20. The pipe is given an initial velocity of 100 m/s. The rigid plate is fixed in space.

#
# Merge a pipe to a plate - complete input deck
*TIME
0.001
#
# Define geometries and mesh
*COMPONENT_PIPE
"pipe"
10, 10, 10, 10, 1
0.0, 0.0, 0.0, 0.0, 0.0, 0.1, 0.02, 0.021
*COMPONENT_BOX
"plate"
20, 20, 10, 10, 1
-0.05, -0.05, -0.01, 0.05, 0.05, 0.0
*CHANGE_P-ORDER
P, 10, 3
#
# Material properties
*MAT_ELASTIC
10, 1500.0, 1.0e8, 0.49
*MAT_RIGID
20, 7800.0
*PART
"pipe"
10, 10, 0, 0, 45.0
"plate"
20, 20
#
# Boundary and initial conditions
*BC_MOTION
"fixed plate"
P, 20, XYZ, XYZ
*INITIAL_VELOCITY
P, 10, 100.0, 0.0, 0.0
*MERGE
"pipe to plate"
P, 10, P, 20
*END
Merge a pipe to a plate
Merge a pipe to a plate