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Can connector element used in frequency step?

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mayaview

Civil/Environmental
Joined
Oct 20, 2014
Messages
4
Location
SG
Since we have following text in the doc, I think the answer is yes, but I can not make it work.

[pre]Defining elastic connector behavior in linear perturbation procedures

Available components of relative motion with connector elasticity use the linearized elastic stiffness from the base state. In direct-solution steady-state dynamic and subspace-based steady-state dynamic analyses, the linear elastic stiffness defined by an uncoupled connector elasticity behavior may be frequency dependent.
[/pre]

The input file is very straightforward as two RP with one connector element:


[pre]
*Heading
*Preprint, echo=NO, model=NO, history=NO, contact=NO
**
** PARTS
**
*Part, name=PART-1
*Node
1, 0., 0., 0.
*Nset, nset=PART-1-REFPT_, internal
1,
*Nset, nset=Set-2
1,
*Element, type=MASS, elset=Set-2_Inertia-1_
1, 1
*Mass, elset=Set-2_Inertia-1_
1.,
*End Part
**
*Part, name=PART-2
*Node
1, 0., 1., 0.
*Nset, nset=PART-2-REFPT_, internal
1,
*Nset, nset=Set-2
1,
*Element, type=MASS, elset=Set-2_Inertia-1_
1, 1
*Mass, elset=Set-2_Inertia-1_
1.,
*End Part
**
**
** ASSEMBLY
**
*Assembly, name=Assembly
**
*Instance, name=PART-1-1, part=PART-1
*End Instance
**
*Instance, name=PART-2-1, part=PART-2
*End Instance
**
*Element, type=CONN3D2
1, PART-2-1.1, PART-1-1.1
*Connector Section, elset=_PickedSet16, behavior=ConnProp-1_CONNSECT-1
Translator,
"Datum csys-2",
*Nset, nset=SET-2, instance=PART-1-1
1,
*Nset, nset=SET-3, instance=PART-2-1
1,
*Nset, nset=SET-4, instance=PART-2-1
1,
*Nset, nset=SET-5, instance=PART-2-1
1,
*Nset, nset=WIRE-1-SET-1, instance=PART-2-1
1,
*Nset, nset=WIRE-1-SET-1, instance=PART-1-1
1,
*Elset, elset=_PickedSet16, internal
1,
*Orientation, name="Datum csys-2"
0., -1., 0., 0., 0., 1.
1, 0.
*End Assembly
*Connector Behavior, name=ConnProp-1_CONNSECT-1
*Connector Constitutive Reference
11., , , , ,
*Connector Elasticity, component=1
10.,
**
** BOUNDARY CONDITIONS
**
** Name: Disp-BC-1 Type: Displacement/Rotation
*Boundary
SET-2, 1, 1
** Name: Disp-BC-2 Type: Displacement/Rotation
*Boundary
SET-2, 2, 2
** Name: Disp-BC-3 Type: Displacement/Rotation
*Boundary
SET-2, 3, 3
** Name: Disp-BC-4 Type: Displacement/Rotation
*Boundary
SET-2, 4, 4
** Name: Disp-BC-5 Type: Displacement/Rotation
*Boundary
SET-2, 5, 5
** Name: Disp-BC-6 Type: Displacement/Rotation
*Boundary
SET-2, 6, 6
** Name: Disp-BC-7 Type: Displacement/Rotation
*Boundary
SET-3, 1, 1
** Name: Disp-BC-8 Type: Displacement/Rotation
*Boundary
SET-3, 3, 3
** Name: Disp-BC-9 Type: Displacement/Rotation
*Boundary
SET-3, 4, 4
** Name: Disp-BC-10 Type: Displacement/Rotation
*Boundary
SET-3, 5, 5
** Name: Disp-BC-11 Type: Displacement/Rotation
*Boundary
SET-3, 6, 6
** ----------------------------------------------------------------
**
** STEP: Step-1
**
*Step, name=Step-1, nlgeom=NO
*Static
1., 1., 1e-05, 1.
**
** OUTPUT REQUESTS
**
*Restart, write, frequency=0
**
** FIELD OUTPUT: F-Output-1
**
*Output, field, variable=PRESELECT
**
** HISTORY OUTPUT: H-Output-1
**
*Output, history, variable=PRESELECT
**
** HISTORY OUTPUT: H-Output-2
**
*Output, history, time interval=0.1
*Node Output, nset=SET-5
U2,
*End Step
** ----------------------------------------------------------------
**
** STEP: Step-2
**
*Step, name=Step-2, nlgeom=NO, perturbation
*Frequency, eigensolver=Lanczos, acoustic coupling=on, normalization=displacement
1, , , , ,
**
** OUTPUT REQUESTS
**
*Restart, write, frequency=0
**
** FIELD OUTPUT: F-Output-2
**
*Output, field, variable=PRESELECT
*End Step
[/pre]

What is wrong in this input file?
 
THREE FACTORIZATIONS IN A ROW FAILED. CHECK THE MODEL. IT IS POSSIBLE THAT THE MODEL CONTAINS THE KINEMATIC COUPLING DEFINITION SET UP IN A WAY THAT A DEGREE OF FREEDOM HAS NEITHER MASS NOR STIFFNESS
 
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