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Can connector element used in frequency step?

Can connector element used in frequency step?

Can connector element used in frequency step?

(OP)
Since we have following text in the doc, I think the answer is yes, but I can not make it work.

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.
 

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


*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
 

What is wrong in this input file?

RE: Can connector element used in frequency step?

(OP)
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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