Lec 07 Superelement NAS105

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S7-1NAS105, Section 7, July 2003

SECTION 7

SUPERELEMENT ANALYSIS


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TABLE OF CONTENTSSection Page

WHAT IS A SUPERELEMENT? 7-9ADVANTAGES OF SUPERELEMENT ANALYSIS 7-10

DISADVANTAGES OF SUPERELEMENT ANALYSIS 7-12

HOW ARE SUPERELEMENTS DEFINED IN MSC.NASTRAN? 7-13

MAIN BULK DATA SUPERELEMENT DEFINITION 7-15

MAIN BULK DATA GRID POINT PARTITIONING 7-16BULK DATA USED TO DEFINE PARTS 7-17

BULK DATA USED TO DEFINE SUPERELEMENTS 7-18

BULK DATA USED TO CONNECT PARTS 7-19

SEBNDRY ENTRYelement Boundary-Point Definition 7-20

SECONCT ENTRY 7-21SEEXCLD ENTRY 7-23

SEBULK ENTRY 7-24

SAMPLE PROBLEM- STEEL STAMPING 7-26

SAMPLE PROBLEMSTEEL STAMPING SAMPLE SUPERELEMENT 1 7-28


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SAMPLE PROBLEMSTEEL STAMPING SESET ENTRIES FOR MAINBULK DATA SUPERELEMENTS 7-33

PARTITIONED SOLUTIONS 7-34

THEORY OF STATIC CONDENSATION 7-36

CONVENTIONAL ANALYSIS 7-38

SUPERELEMENT ANALYSIS 7-41

BULK DATA FOR STATIC LOADS ON SUPERELEMENTS 7-48

SINGLE-POINT CONSTRAINSTS ON SUPERELEMENTS 7-50

MPCs AND RIGID ELEMENTS IN SUPERELEMENTS 7-52

RIGID CONNECTION OF TWO SUPERELEMENTS 7-53

SUPERELEMENT CASE CONTROL COMMANDS 7-54

SUPER COMMAND 7-55

EXPANDED VERSUS CONDENSED 7-56

SUPER COMMAND EXAMPLEONE LOADING CONDITION 7-58

MULTIPLE LOADING CONDITIONS IN SUPERELEMENT CASECONTROLOPTION 1 7-59


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MULTIPLE LOADING CONDITIONS IN SUPERELEMENTCASE CONTROLOPTION 2 7-60

REASONS TO USE OPTION 2 FOR MULTIPLE LOADINGS 7-62

MULTIPLE LOADINGSSAMPLE OF OPTION 1 7-63

MULTIPLE LOADINGSSAMPLE OF OPTION 2 7-64

PARAMETERS IN CASE CONTROL 7-65SAMPLE SUPERELEMENT STATIC RUN INPUT 7-66

SAMPLE SUPERELEMENT STATIC RUN INPUT USING PARTS 7-68

SUPERELEMENT REDUCTION METHODS AVAILABLE IN DYNAMIC ANALYSIS 7-71

DEGREES OF REDUCTION 7-72

COMPARISON OF REDUCTION METHODS 7-73ADVANTAGES OF EACH REDUCTION METHOD 7-74

CALCULATION OF NORMAL MODES USING STATIC REDUCTION ONLY 7-75

CALCULATION OF NORMAL MODES USING DYNAMIC REDUCTIONFOR SUPERELEMENT 7-76


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TABLE OF CONTENTS

Section Page

FIXED BOUNDARY SOLUTIONS (PARAM, FIXEDB, -1) 7-78

PROCEDURES FOR SUPERELEMENT DYNAMIC REDUCTION 7-79

SPECIFICATION OF FIXED AND FREE BOUNDARY DEGREES OF FREEDOM 7-81

REFERENCES FOR CMS 7-82

SUPERELEMENT DYNAMICS EXAMPLE 7-83

APPENDIXTHE CRAIG-BAMPTON MEDTHODHAND-SOLVED EXAMPLE 7-100

DEFAULT CMS METHOD FIXED BOUNDARY CMS 7-101

SOLUTION BY HAND 7-104

SOLUTION USING MSC.NASTRAN SOL 103 7-114

SELECTED OUTPUT FROM MSC.NASTRAN 7-115


7/136S7-7NAS105, Section 7, July 2003

TABLE OF CONTENTS

Section Page

EXTERNAL SUPERELEMENTS 7-117

CREATING AN EXTERNAL SUPERELEMENT 7-118

ATTACHING AN EXTERNAL SUPERELEMENT 7-120

DATA RECOVERY FOR AN EXTERNAL SUPERELEMENT 7-122

ATTACHING AN EXTERNAL SUPERELEMENT 7-123

SAMPLE PROBLEM 7-125

SAMPLE PROBLEM USING MATRIXDB 7-126

SAMPLE PROBLEM USING DMGIOP2 PROGRAM 7-132


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ADVANTAGES OF SUPERELEMENTANALYSIS

Large problems (i.e., allows solving problems that exceed yourhardware capabilities)

Less CPU or wall clock time per run (reduced risk since eachsuperelement may be processed individually)

Partial redesign requires only partial solution (cost).

Allows more control of resource usage Partitioned input desirable

Organization

Repeated components

Partitioned output desirable Organization

Comprehension

Components may be modeled by subcontractors.



ADVANTAGES OF SUPERELEMENTANALYSIS (Cont.)

Multi-step reduction for dynamic analysis

Zooming (or global-local analysis)

Allows for efficient configuration studies (What if...)



DISADVANTAGES OF SUPERELEMENTANALYSIS

Increased overhead due to DMAP compilation anddatabase manipulation and storage

Mandatory static condensation may cancel other costsavings for small models.

All superelements must be linear. Approximations must be made in dynamics for mass

and damping through static, component mode, orgeneralized dynamic reduction.



HOW ARE SUPERELEMENTS DEFINED INMSC.NASTRAN?

Superelements are identified using numbers (SEID). Each superelement (SEID > 0) is defined with its own set of grids,

elements, constraints, loads, etc.

There are two ways to define superelements in MSC.NASTRAN, MainBulk Data Superelements and PARTS (not currently supported for

nonlinear analysis), which allow partitioned input files. Main Bulk Data superelements are easiest thought of as a cookiecutter

approach.

All data provided in the Main Bulk Data section (Between the BEGIN BULK and either

the first BEGIN SUPER = i or ENDDATA entry) is partitioned (divided) into a separate set

for each superelement based on GRID point assignments made by the user

Partitioned bulk data superelements (PARTs) are defined in separate(selfcontained) sections of the input file. The separate PARTs areassembled together based on coincident points.

Each PART is defined in a selfcontained section which begins with a BEGIN SUPER=i

entry and ends with either the next BEGIN SUPER=j entry of the ENDDATA



HOW ARE SUPERELEMENTS DEFINED INMSC.NASTRAN?

The residual structure is a superelement thatcontains grid points, elements, etc. (in the Main BulkData), which are not assigned to any othersuperelement. Last superelement (SEID = 0) to be processed

Superelement on which the assembly analysis (nonlinear, transientresponse, frequency response, buckling, system modes, etc.) isperformed

A superelement may also be defined as an image of

a superelement or obtained from outsideMSC.NASTRAN.



MAIN BULK DATA SUPERELEMENTDEFINITION

Each superelement(SEID > 0) defined in the MainBulk Data section is defined with its own set of grids,elements, constraints, loads, etc. Interior grid points are assigned (partitioned) to a superelement by

the user. Exterior grid points, elements, loads, and constraints are

automatically partitioned by the program based on interior grid pointassignments.



MAIN BULK DATA GRID POINTPARTITIONING

Bulk Data Entries

Only interior points need to be defined.

SESET takes precedence over GRID. For the example shown above, Grid Point 47 will belong to the residual structure

(SEID=0).

Elements, constraints, loads, etc., are automatically partitioned.

SESET THRU option allows open sets.

Points not assigned to any superelement belong to the residualstructure by default. A model with no grid point assignments is definedas a residual structure-only model.

1 2 3 4 5 6 7 8 9 10

GRID GID ETC. SEID

GRID 47 2

1 2 3 4 5 6 7 8 9 10

SESET SEID G1 "THRU" G2

SESET 0 47 THRU 57

Superelements areidentified by an integer.



BULK DATA USED TO DEFINE PARTS

Each PART is defined in a separate section of the input file

The section containing the data for a PART will begin with:BEGIN (BULK) SUPER = i

where i is the superelement id to be defined by the following input

The section containing the data for a PART will end with either:BEGIN (BULK) SUPER = j

where j is the superelement defined in the next section of the input fileor

ENDDATA

which indicates the end of the input file

The Bulk Data for each PART must be selfcontained It must contain all data defining elements, properties, materials, and

loadings for that PART

Different PARTs may use the same id numbers for elements and GRIDpoints, since each is in a selfcontained input section.



BULK DATA USED TO DEFINESUPERELEMENTS

ID test, problemSOL 101CENDTITLE = SAMPLE INPUT FILE DEMONSTRATING PART INPUTSUBCASE 1LOAD = 1DISP = ALLBEGIN BULK$

$ MAIN BULK DATA may be omitted if desired$ contains data defining residual structure and also any Main Bulk Data$ superelements$$ any superelements defined in this section will be defined by$ using SESET entries or field 9 on the GRID entries$BEGIN SUPER = 1$$ model data for PART 1$BEGIN SUPER = 2$$ model data for PART 2$ENDDATA

Sample input stream



BULK DATA USED TO CONNECT PARTS

Since PARTs are selfcontained, it is necessary to connect them to

each other and the Main Bulk Data superelements

The Program will automatically determine coincident grid pointsbetween each PART and any other PARTs or Main Bulk Datasuperelements

If desired, the automatic connection logic may be modified or

overridden by using the following entries in the Main Bulk Data section SEBNDRYdefines a set of points for a PART which may be used in

the automatic search for attachments

SECONCTAllows definition of a tolerance for connection and (ifdesired) manual listing of the grid points being connected

SEEXCLDAllows you to provide a list of points to be excluded fromthe boundary search

SEBULKthe METHOD field on this entry controls whether theAUTO or MANUAL connection logic is used.



SEBNDRY ENTRYDefines a list of grid points in a partitioned superelement for the automatic boundary searchbetween a specified superelement or between all other superelements in the model.

Format:

Example 1:

Example 2:

Field Contents

SEIDA Superelement Identification number. See Remark 2. (Integer 0)

SEIDB Superelement Identification. See Remark 3. (Integer 0 or Character

All ; Default = ALL )

GIDAI Identification number of a boundary grid point in superelement SEIDA.

Remarks:1. SEBNDRY may only be specified in the main Bulk Data Section and is not

recognized after the BEGIN SUPER = n.

2. SEIDA AND SEIDB may reference partitioned superelements or superelements inthe main Bulk Data Section

1 2 3 4 5 6 7 8 9 10

SEBNDRY SEIDA SEIDB GIDA1 GIDA2 GIDA3 GIDA4 GIDA5 GIDA6

GIDA7 GIDA8 etc.

SEBNDRY 400 4 10 20 30 40

SEBNDRY 400 4 10 20 30 40



SECONCT ENTRYExplicitly defines grid and scalar point connection procedures for a partitionedsuperelement.

Format:

Example:

Field Contents

SEIDA Partitioned superelement Identification number. See Remark 2.(Integer > 0)

SEIDB Identification number of superelement for connection to SEIDA.(Integer 0)

TOL Location tolerance to be used when searching for or checking

boundary grid points. (Real; Default = 10E5 )LOC Coincident location check option for manual connection.

(Character; YES or NO; Default = YES)

GIDAI Identification number of a grid or scalar point in superelementSEIDA, which will be connected to GIDBI.

GIDBI Identification number of a grid or scalar point in superelement

SEIDB, which will be connected to GIDAI.

1 2 3 4 5 6 7 8 9 10

SECONCT SEIDA SEIDB TOL LOC

GIDA1 GIDB1 GIDA2 GIDB2 GIDA3 GIDB3 etc.

SECONCT 10 20 1.00E-04 YES

1001 4001 1002 4002 2222 4444


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SEEXCLD ENTRY

Defines grids that will be excluded during the attachment of a partitioned

superelement.Format:

Example:

Field Contents

SEIDA Partitioned superelement Identification number. See Remark 2.(Integer > 0)

SEIDB Superelement Identification. (Integer > 0 or Character = ALL )

GIDAI Identification number of a grid in superelement SEIDA to be

executed from connection to superelement SEIDB.Remarks:

1. SEEXCLD can only be specified in the main Bulk Data Section and isignored after the BEGIN SUPER = n command.

2. SEIDA and SEIDB may reference partitioned superelements orsuperelements defined in the main Bulk Data Section.

1 2 3 4 5 6 7 8 9 10

SEEXCLD SEIDA SEIDB GIDA1 GIDA2 GIDA3 GIDA4 GIDA5 GIDA6

GIDA7 GIDA8 etc.

SEEXCLD 110 10 45 678 396


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SEBULK ENTRY

Defines superelement boundary search options and a repeated, mirrored, or collectorsuperelement.

Format:

Example:

Field Contents

SEID Superelement identification number. (Integer 0)TYPE Superelement type. (Character; No Default)

PRIMARY Primary

REPEAT Identical

MIRROR Mirror

COLLCTR Collector

EXTERNAL External

RSEID Identification number of the reference superelement, used if TYPEREPEAT and MIRROR. (Integer 0; Default 0)

METHOD Method to be used when searching for boundary grid points. (Character:AUTO or MANUAL; Default = AUTO)

TOL Location tolerance to be used when searching for boundary grid points.(Real; Default 10E5)

LOC Coincident location check option for manual connection option.(Character: YES or NO; Default = YES)

1 2 3 4 5 6 7 8 9 10

SEBULK SEID TYPE RSEID METHOD TOL LOC

SEBULK 14 REPEAT 4 AUTO 1.00E-03


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SEBULK ENTRY (Cont.)

Remarks:

1. The TYPE = REPEAT or MIRROR does not include superelementsupstream of the reference superelement. A repeated or mirroredsuperelement can have boundaries, loads, constraints, and reductionprocedures that are different than the reference superelement.

2. METHOD = MANUAL requires SECONCT entries. SEBNDRY and

SEEXCLD, which reference SEID, will produce a fatal message.

3. SECONCT, SEBNDRY, and SEEXCLD entries can be used to augmentthe search procedure and/or override the global tolerance.

4.For combined automatic and manual boundary search, the METHOD =AUTO should be specified and connections should be specified on a

SECONCT entry.

5.TOL and LOC are the default values that can be modified between two

superelements by providing the required tolerance on the SECONCT entry.6.TYPE = MIRROR also requires specification of a SEMPLN entry.

7.TYPE = COLLCTR indicates a collector superelement, which does notcontain any grids or scalar points.

8.For TYPE = EXTERNAL, see also PARAM, EXTOUT, etc. description inSection 6 of the MSC.NASTRAN Quick Reference Guide.


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SAMPLE PROBLEM- STEEL STAMPING


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SAMPLE PROBLEM- STEEL STAMPING(Cont.)

Grid Points 1 and 2 fixed

Material properties:Steel t = 0.05

E = 29 x 106psi

= 0.3= 0.283 lb/in3(weight density)

Applied loads 1 psi pressure on square portions

Normal force of 2 lb on Grids 93 and 104

Opposing normal force of 2 lb on Grids 93 and 104


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SAMPLE PROBLEMSTEEL STAMPINGSAMPLE SUPERELEMENT 1


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SAMPLE PROBLEMSTEEL STAMPING(Cont.)

Grids 1 and 2 are fixed

Steel D = .06

E = 20 x 106psi

D = . 3= .283 lb./In3(weight density)

Applied Loads1. Pressure on square portions of 1 psi

2. Normal force of 2 lb on Grids points 93 and 104

3. Opposing normal forces of 2lb on Grid points 93 and 104

SE# Elements

1 18

42

2 43 87

3 14 15

4 16 17

5 6 9

6 10 13

7 1 4

0 5


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MODEL DEFINITION FOR SAMPLEPROBLEM

BEGIN BULK

$

$*******************************************************************

$ BASIC MODEL DEFINITION - SAME FORALL RUNS

$*******************************************************************

$

GRDSET,,,,,,,6

GRID,1,,-.4,0.,0.,,123456

GRID,3,,-.4,0.9,0.=,*2,=,=,*.9,==

=1

GRID,2,,.4,0.,0.,,123456

GRID,4,,.4,0.9,0.

=,*2,=,=,*.9,==

=1

GRID,9,,-3.6,3.6,0.

=,*1,=,*.8,==

=8

GRID,19,,-3.6,4.4,0.

=,*1,=,*.8,===8

GRID,29,,-3.6,5.2,0.

GRID,30,,-2.8,5.2,0.

GRID,31,,2.8,5.2,0.

GRID,32,,3.6,5.2,0.

GRID,33,,-5.2,6.,0.

=,*1,=,*.8,==

=4

GRID,39,,1.2,6.,0.

=,*1,=,*.8,==

=4GRID,45,,-5.2,6.8,0.

=,*1,=,*.8,==

=4

GRID,51,,1.2,6.8,0.

=,*1,=,*.8,==

=4

GRID,57,,-5.2,7.6,0.

=,*1,=,*.8,==

=4

GRID,63,,1.2,7.6,0.=,*1,=,*.8,==

=4

GRID,69,,-5.2,8.4,0.

=,*1,=,*.8,==

=4

GRID,75,,1.2,8.4,0.

=,*1,=,*.8,==

=4

GRID,81,,-5.2,9.2,0.

=,*1,=,*.8,==

=4GRID,87,,1.2,9.2,0.

=,*1,=,*.8,==

=4

GRID,93,,-5.2,10.,0.

=,*1,=,*.8,==

=4

GRID,99,,1.2,10.,0.

=,*1,=,*.8,==

=4


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MODEL DEFINITION FORSAMPLE PROBLEM (Cont.)

$

$ ELEMENTS

$

CQUAD4,1,1,1,2,4,3

=,*1,=,*2,*2,*2,*2

=1

CQUAD4,4,1,7,8,14,13

CQUAD4,6,1,9,10,20,19

=,*1,=,*1,*1,*1,*1

=2

CQUAD4,5,1,13,14,24,23CQUAD4,10,1,14,15,25,24

= *1,=,*1,*1,*1,*1

=2

CQUAD4,14,1,19,20,30,29

CQUAD4,15,1,29,30,36,35

CQUAD4,16,1,27,28,32,31

CQUAD4,17,1,31,32,42,41

CQUAD4,18,1,33,34,46,45

=,*1,=,*1,*1,*1,*1

=3

CQUAD4,23,1,45,46,58,57

=,*1,=,*1,*1,*1,*1

=3

CQUAD4,28,1,57,58,70,69

=,*1,=,*1,*1,*1,*1

=3

CQUAD4,33,1,69,70,82,81

=,*1,=,*1,*1,*1,*1

=3

CQUAD4,38,1,81,82,94,93

=,*1,=,*1,*1,*1,*1

=3

CQUAD4,43,1,39,40,52,51

=,*1,=,*1,*1,*1,*1

=3

CQUAD4,48,1,51,52,64,63

=,*1,=,*1,*1,*1,*1

=3

CQUAD4,53,1,63,64,76,75

=,*1,=,*1,*1,*1,*1=3

CQUAD4,58,1,75,76,88,87

=,*1,=,*1,*1,*1,*1

=3

CQUAD4,63,1,87,88,100,99

=,*1,=,*1,*1,*1,*1

=3

MAT1,1,30.+6,,.3,.283

PARAM,WTMASS,.00259

PSHELL,1,1,.05,1,,1

$

$ LOADINGS

$

$ LOAD CASE 1 - PRESSURE LOAD

$

PLOAD2,101,-1.,18,THRU,42

PLOAD2,101,-1.,43,THRU,67

$


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MODEL DEFINITION FORSAMPLE PROBLEM (Cont.)

$ LOAD CASE 2 - 2 POINT LOADS AT CORNERS

$

FORCE,201,93,,2.,0.,0.,1.

FORCE,201,104,,2.,0.,0.,1.

$

$ LOAD CASE 3 - OPPOSING POINT LOADS AT

CORNERS

$

FORCE,301,93,,2.,0.,0.,1.

FORCE,301,104,,2.,0.,0.,-1.

$

****************************************

***************************

$ END OF BASIC MODEL DEFINITION

$

****************************************

***************************ENDDATA


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PARTITIONED SOLUTIONS

For each superelement, its degrees-of-freedom (DOFs) aredivided into two subsets: Exterior DOFs (called the A-set): Designates the analysis DOFs, which are

retained for subsequent processing (for Superelement 1, Grid Points 35 and36)

Interior DOFs: Designates the DOFs that are reduced out during

superelement processing and are omitted in subsequent processing (forSuperelement 1 of the sample problem, Grid Points 33, 34, 37,38, 4550,5762, 6974, 8186, 939 8).

The Main Bulk Data is partitioned by superelement (although thefollowing operations are performed using tables, it is easier tothink of them in terms of the Bulk Data). All Bulk Data unique to the superelement is removed from the original input

and placed into a unique set for the superelement.

Bulk Data that is shared or used by more than one superelement (ex:

PSHELL, MAT1, etc.) is copied for each applicable superelement.

PARTs are already separated.


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PARTITIONED SOLUTIONS (Cont.)

For each superelement, the program produces a description in

matrix terms of its behavior as seen at the boundary or exteriordegrees of freedom. A set of G-sized matrices is produced for each superelement based on the

input data.

These matrices are reduced down to matrices representing the properties of thesuperelement as seen by the adjacent (attached) structure.

At the residual structure, the program combines and assemblesthe boundary matrices. The BULK DATA for the RESIDUAL consists of all residual Main Bulk Data

not assigned to any superelement plus any common data.

Solve for the residual structure displacements.

For each superelement, expand boundary (exterior)displacements to obtain its interior displacements.


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THEORY OF STATIC CONDENSATION

After generating matrices and applying MPCs and SPCs,

O-Set = Interior points (to be condensed out by the reduction)

A-Set = exterior (or boundary) points (which are retained forfurther analysis)

Partition

Extract upper equation and pre-multiply by

Let (Boundary Transformation)

and (Fixed Boundary Displacements)

then (Total Interior Displacements)

ffff PUK

a

o

a

o

aaT

oa

oaoo

P

P

U

U

KK

KK

1

ooK

o1

ooaoaooo1

oo PK]UKU[KK

o1

oooo

oa1

oooa

PKU

KKG

aoaooo UGUU

THEORY OF STATIC


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THEORY OF STATICCONDENSATION(Cont.)

Substitute expression for U o in the lower equation

then (Boundary Stiffness)

and (Boundary Loads)

Solve for residual structure

(Boundary displacements)

aaaaooaoa

Toa PUK]UU[GK

aaoaToaaa KGKK

aoToaa PPGP

a-1aaa PKU


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CONVENTIONAL ANALYSIS

Flowchart

Generation

Solution


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CONVENTIONAL ANALYSIS(Cont.)

Generation

4545

45453434

34342323

23231212

1212

GG

KK000

KKKK00

0KKKK0

00KKKK

000KK

][K

1000

00

00

00

0001

KGG

1

121

121

121

1


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CONVENTIONAL ANALYSIS(Cont.)

Apply Constraints and Solve

4

3

21

453434

34342323

232312

4

3

2

P

P

P

KKK

KKKK

KKK

U

U

U

3

2

1

U

U

U 1

4

3

2

210

121

012

3.5

4.0

2.5

U

U

U

4

3

2


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SUPERELEMENT ANALYSIS

Flowchart

DO LABELA

I = 1, NSE

Phase I

Generation

Assembly

Reduction

LABELA

Phase IISolution

DO LABELB

I = 1, NSE

Phase III

Data Recovery

LABELB


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SUPERELEMENT ANALYSIS (Cont.)

GenerationSEID = 1

Residual Structure

2323

23231212

1212

1gg

KK0

KKKK

0KK

][K


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ReductionSEID = 1

Eliminate constraints:

Compute boundary transformation:

0

1

0

P

P

P

}{P13

2

1

1g

aaao

oaoo

2323

2323121ff

KK

KK

KKKKK][K

0.5KK

K

][K][K][G

2312

23

oa1

oo1

oa


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Compute boundary stiffness:

Compute boundary loading:

0.5KK

KKK

]GKK[][K

2312

23121aa

oaToaaa

1aa

a

0

13

21f

P

P

0

1

P

P}{P

0.5P

KK

KPP

}PGP{}{P

2

2312

2313

13

oToaa

1a

0


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SimilarlySEID = 2

0

3

0

P

P

P

}{P

KK0

KKKK

0KK

][K

5

4

23

2g

4545

45453434

3434

2gg

.5P

KK

K

0.5KK

KK

0.5KK

K

4

4534

34

4534

4534

4534

34

1PP

]K[

]G[

2

32

3

2

aa

2

oa

0


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SUPERELEMENT ANALYSIS (Cont.)Residual Structure

Assembly

Solution4PPPP

}PP{P}{P

1KKK

]KK[K][K

03

23

13

0g

2a

1aa

21

0gg

2aa

1aaaa

4K

PU

}{P][K}{U

03

a1

aaa

0


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SUPERELEMENT ANALYSIS (Cont.)Data RecoverySEID = 1

Enforce (transform) boundary motion.

Compute fixed-boundary motion.

Compute total motion.

2.0UKK

KU

}]{U[G}{U

32312

2332

aoaao

0.5PKK

1U

}{P][K}{U

22312

o2

o-1

oooo

2.5KK

PUKU

}{U][U}{U

2312

23232

ao

ooo

BULK DATA FOR STATIC LOADS ON


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BULK DATA FOR STATIC LOADS ONSUPERELEMENTS

Main Bulk Data Superelements: Loads applied to interior grid points are assigned to the

superelement.

Loads applied to exterior grid points are assigned to the mostdownstream superelement, that is, the superelement for which thegrid point is interior.

Loads applied to elements (PLOADi) are assigned in the samemanner as elements.

Note: A PLOAD entry may not reference the interior points of morethan one superelement.

Partitioned Superelements: Any Loadingrelated entries must be defined in the partitioned data

(in the area of the input file beginning with BEGIN SUPER =)

STATIC LOADS ON MAIN BULK DATA


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STATIC LOADS ON MAIN BULK DATASUPERELEMENTS

Example

SESET, 1, 4, 5, 6 Grids 4, 5, and 6 are interior points to Superelement 1. Point 3 is exterior to Superelement 1.

P2 is assigned to Superelement 0.

W and P1is assigned to Superelement 1.

Superelement 0Superelement 1

SINGLE POINT CONSTRAINSTS ON


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MAIN BULK DATA SUPERELEMENTS Constraint entries applied to the interior points of a superelement

are assigned to that superelement.

Constraint entries applied to the exterior points of a superelementare sent downstream.

Multiple boundary conditions are allowed for the residual structureonly

For multiple boundary conditions, place grid points that will beconstrained interior to the residual structure.

Each superelement may have only one SPC set per run.

PARTITTIONED SUPERELEMENTS All constraintrelated bulk data entries for the interior points of a

PART must be defined in the partitioned bulk data

(BEGIN SUPER=).

SINGLE-POINT CONSTRAINSTS ONSUPERELEMENTS

SINGLE POINT CONSTRAINSTS ON


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SINGLE-POINT CONSTRAINSTS ONSUPERELEMENTS (Cont.)

SESET, 1, 4,5, 6 Grid Points 4, 5, and 6 are interior to Superelement 1.

Point 3 is exterior to Superelement 1.

SPC at 3 is assigned to Superelement 0.

SPC at 6 is assigned to Superelement 1.

Superelement 0 Superelement 1

MPCs AND RIGID ELEMENTS IN


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MPCs AND RIGID ELEMENTS INSUPERELEMENTS

Rigid elements and MPCs that connect only interiorpoints are modeled conventionally.

Dependent degrees of freedom may not be exterior.

For MPCs and rigid elements that connect two

superelements, Place the upstream degrees of freedom in the dependent set.

Place the downstream degrees of freedom in the independent set.

Multiple multipoint constraint conditions are allowed

for the residual structure only For multiple multipoint constraints, place grid points that will bespecified on these interior to the residual structure.

Each superelement may have only one MPC set per run. (Note:MPCADD may be used.)


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SUPERELEMENT CASE CONTROL


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SUPERELEMENT CASE CONTROLCOMMANDS

SE-type (manual processing)SEMG, SELG, SEKR, SELR,SEMR, SEDR, and SEALLappear above the first SUBCASE ifused

Control solution sequence execution

Make no requests for loads, constraints, or output

SEALL combines SEMG, SELG, SEKR, SELR, and SEMR

Not necessary in SOL 101 and higher (default is SEALL=ALL, which impliesthat all necessary processing will be performed)

Superelement processing order controlappear above the firstSUBCASE if used

SEFINALLast superelements to be processed before residual structure

not recommended SEEXCLUDESuperelements not to be assembled downstream

Case Control partitioningSUPER

Assigns a subcase(s) to a specific superelement(s)

Appears above or below subcase level


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SUPER COMMAND

Partitions (assigns) a subcase to a superelement(s)

Associates a superelement(s) with requests for parameters, loads,constraints, and output

PreV69If the Case Control Section does not contain a SUPERcommand, then loads, constraints, and output requests are applied to theresidual structure only (the old default was SUPER = 0).

V69 The new default is SUPER=ALL. if no SUPER command is present,

the subcases are assumed to apply to ALL superelements (if any SUPERcommands occur in the Case Control, the default reverts to SUPER=0 forupward compatibility).

The SUPER command may reference a superelement or a SET ofsuperelements.

Note: The SET ID must be unique with respect to any superelement IDs.

Form of SUPER commandSUPER = i, j

where i = superelement ID or set of superelements

j = load sequence number (a counter on loading conditions)


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EXPANDED VERSUS CONDENSED

Conventional Case Control Expanded

Condensed

SUBCASE 10SET 1 = 101 THRU 110DISP = 1LOAD = 100

SUBCASE 20SET 1 = 101 THRU 110DISP = 1

LOAD = 200SUBCASE 30SET 3 = 201 THRU 210DISP = 3LOAD = 200

SET 1 = 101 THRU 110SET 3 = 201 THRU 210DISP = 1LOAD = 200SUBCASE 10LOAD = 100SUBCASE 20SUBCASE 30DISP = 3


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EXPANDED VERSUS CONDENSED(Cont.)

Superelement Case Control Expandedone loading condition

Condensed

$ model with superelements 10, 20, 0DISP = ALLSUBCASE 1 $ SE 10

SUPER = 10LOAD = 100

SUBCASE 2 $ SE 20SUPER = 20LOAD = 100

SUBCASE 101 $ RESIDUAL STRUCTURESET 999 = 0SUPER = 999LOAD = 100

BEGIN BULK

SUBCASE 1

DISP = ALL

LOAD = 100

BEGIN BULK


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MULTIPLE LOADING CONDITIONS IN


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SUPERELEMENTCASE CONTROLOPTION 1

Appears identical to conventional Case Control

For each loading, create one subcase (use thedefault SUPER=ALL)

Option 1 requires All superelements must use the same loading, SPC, and MPC sets.

MULTIPLE LOADING CONDITIONS IN


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SUPERELEMENTCASE CONTROLOPTION 2

For the residual structure Define a subcase for each loading condition.

For each superelement (or set of superelements) Define a subcase for each loading condition using a SUPER command

identifying the superelement (or a set of superelements) and the loading

sequence number.

SUBCOMs are treated as a new load sequence and, therefore,must have a SUPER command and the residual structure musthave a corresponding subcase or subcom.

REPCASEs must immediately follow the subcase they reference

and contain the same SUPER=i,j command.

MULTIPLE LOADING CONDITIONS


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MULTIPLE LOADING CONDITIONSEXAMPLE -- OPTION 2

SEALL = ALL

DISP = ALL

SPC = 10SUBCASE 1 $ SEID 10 LOAD SEQ 1

SUPER = 10, 1

LOAD = 100

SUBCASE 2 $ SEID 10 LOAD SEQ 2

SUPER = 10, 2

ELFORCE = ALL

SUBCASE 12 $ SEID 20 LOAD SEQ 2

SUPER = 20, 2

LOAD = 200

SUBCASE 101 $ R.S. LOAD SEQUENCE 1

SUPER = 0,1

GPFOR = ALL

SUBCASE 102 $ R.S. LOAD SEQUENCE 2

SUPER = 0,2

LOAD = 1000

DISP ELSTRE ELFOR10 100 X

20

0 X X

10 X X

20 200 X

0 1000 X

1

2

Load

SEQ

Output Requests

SEID

Load

Set ID

REASONS TO USE OPTION 2 FOR


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REASONS TO USE OPTION 2 FORMULTIPLE LOADINGS

It allows different LOAD, SPC, MPC IDs, etc., foreach superelement.

Each superelement may have unique outputrequests.

It may be the only way to perform an analysis ifgroups have not coordinated their efforts.

MULTIPLE LOADINGS SAMPLE OF


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MULTIPLE LOADINGSSAMPLE OFOPTION 1

Coordinated input allows for simple Case Control P1and W1are applied for loading 1

P2is applied for loading 2

SOL 101TIME 5

CENDTITLE = SAMPLE OF OPTION 1 FOR MULTIPLE LOADINGSDISP = ALL $ DEFAULT CASE CONTROL BEFORE FIRST$ SUPER = ALL is now the defaultSUBCASE 1LOAD = 1SUBCASE 2LOAD = 2BEGIN BULK..ENDDATA

Superelement 0

Superelement 1

MULTIPLE LOADINGS SAMPLE OF


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MULTIPLE LOADINGS SAMPLE OFOPTION 2

Uncoordinated input forces complicated Case Control P1 and W 1 are applied for loading 1 for Superelement 1.

P2 is applied for loading 1 on the residual structure. P1 is applied on the residual structure for loading 2.

SOL 101TIME 5CENDTITLE = UNCOORDINATED INPUT FORCES COMPLEX CASE CONTROLDISP = ALLSET 99 = 0SUBCASE 1SUPER = 1,1 $ S.E. 1, LOAD CONDITION 1

LOAD = 1SUBCASE 2SUPER = 99,1 $ R.S., LOADING 1LOAD = 2SUBCASE 11SUPER = 1,2 $ S.E. 1, LOAD CONDITION 2$ NO LOADS APPLIED DIRECTLY ON S.E. 1 SUBCASE ONLY FOR$ DATA RECOVERYSUBCASE 12SUPER = 99,2 $ R.S., LOAD CONDITION 2LOAD = 1BEGIN BULK.

ENDDATA

Superelement 0Superelement 1

PARAMETERS IN CASE CONTROL


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PARAMETERS IN CASE CONTROL

Allows changes between superelements on same run

Most, but not all, can be used in Case Control. There is a hierarchical rule for what value used will

be. Subcase value first

Above subcase level value if not in a subcase

Bulk Data value if not in either of the above

Default value if not in any of the above The default is taken from the main subDMAP if one exists.

If not in main subDMAP from the called subDMAP

If NDDL, the default is from the NDDL default table.

Recommendations Specify the parameter value for each subcase (safe).

or

Specify the default value above the subcase level and exceptionswithin subcases.

SAMPLE SUPERELEMENT STATIC RUN


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INPUTID SE, SAMPLE PROBLEM SOL 101

$

$ SUPERELEMENT STATICS SAMPLE PROBLEM STATIC SOLUTION

$ USING SIMPLE CASE CONTROL

$

SOL 101 $ SUPERELEMENT STATICS SINGLE LEVEL TREE

TIME 15

CEND

TITLE = S.E. SAMPLE PROBLEM 1

SUBTITLE = S.E. STATICSRUN 1 MULTIPLE LOADS

DISP = ALL

PARAM,GRDPNT,0

SUBCASE 101

LABEL = PRESSURE LOAD

LOAD = 101

$

SUBCASE 201

LABEL = 2# NORMAL LOADS

LOAD = 201

$

SUBCASE 301

LABEL = OPPOSING LOADS

LOAD = 301$

$

BEGIN BULK

PARAM,POST,0

$

INCLUDE seset.dat

INCLUDE model.dat

INCLUDE load1.dat

$

ENDDATA

Filese1s101.dat



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SAMPLE SUPERELEMENT STATIC RUNINPUT (Cont.)

$ FILE LOAD1.DAT

$

$ LOADINGS FOR RUN SHOWING CONVENTIONAL CASE CONTROL

$

$ LOAD CASE 1 PRESSURE LOAD

$

$ NOTE: THRU RANGE SHOULD INCLUDE ELEMENTS OF ONLY ONE SUPERELEMENT

$PLOAD2,101,1.,18,THRU,42

PLOAD2,101,1.,43,THRU,67

$

$ LOAD CASE 2 2 POINT LOADS AT CORNERS

$

FORCE,201,93,,2.,0.,0.,1.

FORCE,201,104,,2.,0.,0.,1.

$

$ LOAD CASE 3 OPPOSING POINT LOADS AT CORNERS

$FORCE,301,93,,2.,0.,0.,1.

FORCE,301,104,,2.,0.,0.,1.

$

Fileload1.dat



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SAMPLE SUPERELEMENT STATIC RUNINPUT USING PARTS

$ file se1s101p.datSOL 101

CEND

TITLE = S.E. SAMPLE PROBLEM 1 USING PARTs

SUBTITLE = S.E. STATICS RUN 1 MULTIPLE LOADS

DISP = ALL

stress = all

PARAM,GRDPNT,0

PARAM,WTMASS,.00259

SUBCASE 101

LABEL = PRESSURE LOAD

LOAD = 101

$

SUBCASE 201

LABEL = 2# NORMAL LOADS

LOAD = 201

$

SUBCASE 301

LABEL = OPPOSING LOADS

LOAD = 301BEGIN BULK

include part0.dat $ main bulk data section

begin super=1

$

include loadprt1.dat

include part1.dat

begin super=2

Filese1s101p.DAT

$include loadprt2.datinclude part2.dat

begin super=3$include part3.dat




begin super=7$include part7.datenddata



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$

$ file loadprt1.dat

$ loads on s.e. 1

$


$

PLOAD2,101,1.,18,THRU,42$


$

FORCE,201,93,,2.,0.,0.,1.

$


$

FORCE,301,93,,2.,0.,0.,1.

$

Fileloadprt1.dat



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$

$ file loadprt2.dat

$ loads on s.e. 2

$


$PLOAD2,101,1.,43,THRU,67

$


$

FORCE,201,104,,2.,0.,0.,1.

$


$

FORCE,301,104,,2.,0.,0.,1.

$

Fileloadprt2.dat

SUPERELEMENT REDUCTION METHODS


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SUPERELEMENT REDUCTION METHODSAVAILABLE IN DYNAMIC ANALYSIS

Static reduction Static condensation of stiffness and Guyan reduction of mass

Static reduction is the default

Dynamic reduction Generalized dynamic reduction (GDR) (not recommended) Component modal synthesis (CMS)

Analytical (All SE dynamic SOLs)

DEGREES OF REDUCTION


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DEGREES OF REDUCTION

Static reduction (default)

Interior masses relumped to boundary (Guyan) Rigid body properties preserved

Important masses must be made exterior (boundary)

Generalized dynamic reductionin addition to static reduction

Interior masses represented by approximate eigenvectors

Approximate natural frequencies and mode shapes may be output

Component mode reductionin addition to static reduction

Interior masses represented by calculated eigenvectors of the component

Eigensolutions for each superelement may be output

All reductions are performed using a set of transformation

vectorsthese vectors are best thought of as Ritz vectors

COMPARISON OF REDUCTION METHODS


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COMPARISON OF REDUCTION METHODS

Static reduction

Generalized dynamic reduction

Approximate eigenvectors are used to represent the interior

motion. Component mode reduction

Exact eigenvectors are used to represent the interior motion.

}{U}]{u[G}{U oototo

0 Local dynamic effectsare ignored.

q

t

oqoto U

U]G[G}{U

q

t

oqoto U

U]G[G}{U

ADVANTAGES OF EACH REDUCTION


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ADVANTAGES OF EACH REDUCTIONMETHOD

Advantages of Component Mode Reduction overStatic Reduction Can use experimental results

More accurate for the same number of dynamic DOFs

Ideal for highly coupled and uncoupled structures

Advantages of Static Reduction over ComponentMode Reduction Cheaper

Less sophisticated

CALCULATION OF NORMAL MODESUSING


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USINGSTATIC REDUCTION ONLY

This is the default method used to reducesuperelements is always be performed

Superelement mass, damping, and stiffness arereduced statically to exterior DOFs.

Case Control is similar to static analysis with theaddition of a METHOD command under the residualstructure subcase.

CALCULATION OF NORMAL MODESUSING DYNAMIC REDUCTION FOR


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USING DYNAMIC REDUCTION FORSUPERELEMENT

Dynamic reduction of superelements is optional and is performed inaddition to static (Guyan) reduction if requested

The behavior of a superelement is represented by its real modes inaddition to the static shapes.

The superelement stiffness, mass, and damping are transformed usingboth physical and modal variables.

The superelement modes are computed if a METHOD command appearsunder the superelement subcase and SEQSETi entries are specified forthe superelement (QSETi or SENQSET for PARTs).

The number of superelement modes computed (modal truncation) iscontrolled by the EIGRL entry.

The number of superelement modes sent downstream is controlled by the

number of Qset DOFs provided. SEQSETi entries can reference GRID points or SPOINTs

By default, superelement modes are computed with all exterior degrees offreedom fixed (in the B-set). This is better known as the Craig-Bamptonmethod.


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FIXED BOUNDARY SOLUTIONS


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(PARAM, FIXEDB, -1)Statics

Allows output of the superelement component modes in dynamics

where z implies superelement component modes

v indicates the v-set ( 0 + R + C)

Allows checkout of one superelement at a timedisplacements,stresses, deformed plots, etc.any standard data recovery option.

In SOL 63 after checkout, PARAM,RESDUAL,1 may be used to restartfor system (residual structure) modes.

}]{[G}{U}{ ooo ao UU

0.0 if FIXEDB = -1

Motion Due toBoundary

Displacements

Motion Due to InteriorLoads

Total Motion ofInterior Points

0]] [MK[ vzww

Superelement Modes (ArePrinted if FIXEDB = -1)


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PROCEDURES FOR SUPERELEMENT


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DYNAMIC REDUCTION (Cont.)

Residual structure If static reduction is desired, specify selected physical DOFs in the

A-set.

Note: If CMS has been performed for upstream superelements, thegeneralized coordinates from the superelements should be inthe A-set in order to be included in the final solution.

If GDR or residual structure CMS is used, no physical DOFs in A-set are required.

SPECIFICATION OF FIXED AND FREE


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BOUNDARY DEGREES OF FREEDOM

Set Definition

B Fixed during GDR or CMR

C Free during GDR or CMR

Entry Type

SECSETi No No Yes Yes

SEBSETi No Yes No Yes

Undefined Exterior

DOFs Placed In

B C B B

Present?

REFERENCES FOR CMS


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REFERENCES FOR CMS

W. C. Hurty, Dynamic Analysis of Structural Systems Using

Component Modes, AIAA Journal, Vol. 3, No. 4, April 1965 (Based

upon JPL Tech. Memo 32-530, January 1964).

R. H. MacNeal, A Hybrid Method of Component Mode Synthesis,

Computers & Structures, Vol. 1, 1971.

R. R. Craig and M. C. C. Bampton, Coupling of Substructures for

Dynamic Analysis, AIAA Journal, Vol. 6, No. 7, July 1968.

W. A. Benfield and R. F. Hruda, Vibration Analysis of Structures byComponent Mode Substitution, presented at AIAA/ASME 11th

Structures, Structural Dynamics, and Materials Conference, Denver,CO, April 1970.

S. Rubin, An Improved Component-Mode Representation, presented

at AIAA/ASME 15th Structures, Structural Dynamics, and MaterialsConference, Las Vegas, NV, April 1974.

R. R. Craig, Structural Dynamics: An Introduction to ComputerMethods, John Wiley and Sons, New York, 1981.

E. D. Bellinger, Component Mode Synthesis for External

Superelements, MSR-71, Los Angeles, May 1981, (SOLs 41, 42, 43).

SUPERELEMENT DYNAMICS EXAMPLE


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Cantilever beam modeled with two superelements

Beam properties

A = 5 in2

I = 50.66059 in4

Material properties

E = 10,000,000 psi

p = 0.01 lb-sec2 / in4



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(Cont.)

Compute first five system modes using the followingtechniques: Static reduction

Assume fixed exterior points.

Generalized dynamic reduction (GDR)

Component mode reduction (CMR) GDR and CMR

Assume all free exterior points with CMR.



85/136


(Cont.)

$ FILE SEDYNBLK.DAT

$

DYNRED,1,100.

EIGR,37,MGIV,,,,5

SPC1,10,26,1001

SPC1,10,1345,1001,THRU,1011

SPC1,10,1345,2001,THRU,2016

RBE2,1001,1011,26,2001

GRID,1001,,0.

=,(1),=,(2.),===(9)

GRID,2001,,20.

=,(1),=,(2.),==

=(14)

CBAR,111,10,1001,1002,,1.

=,(1),=,(1),(1),==

=(8)

CBAR,211,10,2001,2002,,1.

=,(1),=,(1),(1),==

=(13)

PBAR,10,10,5.,50.66059,12.66516

MAT1,10,1.+4,,.3,.01

PARAM,COUPMASS,1

Bulk Data Input


86/136

SUPERELEMENT DYNAMICS EXAMPLE(C )


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(Cont.)

Static Reduction Only (Cont.)SUPERELEMENT CMS SAMPLE RUN 1 MAY 2, 1990 MSC.NASTRAN 1/ 4/ 89 PAGE 20

SUPERELEMENT 0

R E A L E I G E N V A L U E S

MODE EXTRACTION EIGENVALUE RADIANS CYCLES GENERALIZED GENERALIZED

NO. ORDER MASS STIFFNESS

1 1 2.004165E+01 4.476790E+00 7.125033E01 1.000000E+00 2.004165E+01

2 2 7.878806E+02 2.806921E+01 4.467353E+00 1.000000E+00 7.878806E+023 3 6.215354E+03 7.883752E+01 1.254738E+01 1.000000E+00 6.215354E+03

4 4 2.425566E+04 1.557423E+02 2.478715E+01 1.000000E+00 2.425566E+04

5 5 6.681884E+04 2.584934E+02 4.114050E+01 1.000000E+00 6.681884E+04

SUPERELEMENT DYNAMICS EXAMPLE(C )


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(Cont.)

Generalized Dynamic Reduction Assign to the residual structure only the

superelement endpoints that are assumed to be fixedfor GDR.

Specify Q-set (SEQSET1) along with thecorresponding variables (SPOINT).

Request GDR (DYNRED) for both superelementsand eigensolution (METHOD) for the residual

structure.

SUPERELEMENT DYNAMICS EXAMPLE(C t )


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(Cont.)$ FILE = SEDYN2.DAT

$

SOL 103

TIME 5

CEND

TITLE = SUPERELEMENT CMS SAMPLE RUN 2

$SEALL = ALL $ ONLY REQUIRED IF SOL


90/136


(Cont.)

SUPERELEMENT CMS SAMPLE RUN 2 JUNE 26, 1990 MSC. NASTRAN 10/ 20/ 89 PAGE 15SUPERELEMENT 100

*** USER INFORMATION MESSAGEPROCESSING OF SUPERELEMENT 100 IS NOW INITIATED.

^^^ PHASE 1 SUPERELEMENT GENERATION, ASSEMBLY AND REDUCTION.

*** USER INFORMATION MESSAGE 4158STATISTICS FOR SYMMETRIC DECOMPOSITION OF

DATA BLOCK SCRATCH FOLLOW NUMBER OF NEGATIVE TERMS ON FACTOR DIAGONAL = 2

*** USER INFORMATION MESSAGE 4181NUMBER OF ROOTS BELOW 0.1000E+ 03 CYCLES IS 2

NUMBER OF GENERALIZED COORDINATES SET TO 6

SUPERELEMENT CMS SAMPLE RUN 2 JUNE 26,1990 MSC.NASTRAN 10/20/ 89 PAGE 16

SUPERELEMENT 200*** USER INFORMATION MESSAGEPROCESSING OF SUPERELEMENT 200 IS NOW INITIATED.

^^^ PHASE 1 SUPERELEMENT GENERATION, ASSEMBLY AND REDUCTION.

*** USER INFORMATION MESSAGE 4158STATISTICS FOR SYMMETRIC DECOMPOSITION OF

DATA BLOCK SCRATCH FOLLOW

NUMBER OF NEGATIVE TERMS ON FACTOR DIAGONAL = 3

*** USER INFORMATION MESSAGE 4181NUMBER OF ROOTS BELOW 0.1000E+ 03 CYCLES IS 3

Generalized Dynamic Reduction (Cont.)



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(Cont.)

NUMBER OF GENERALIZED COORDINATES SET TO 6

SUPERELEMENT CMS SAMPLE RUN 2 JUNE 26, 1990 MSC.NASTRAN 10/ 20/ 89 PAGE19

SUPERELEMENT 0




1 1 2.004111E+01 4.476730E+00 7.124937E01 1.000000E+00 2.004111E+01

2 2 7.870997E+02 2.805530E+01 4.465139E+00 1.000000E+00 7.870997E+02

3 3 6.171406E+03 7.855830E+01 1.250294E+01 1.000000E+00 6.171406E+03

4 4 2.370312E+04 1.539582E+02 2.450320E+01 1.000000E+00 2.370312E+04

5 5 6.478747E+04 2.545338E+02 4.051031E+01 1.000000E+00 6.478747E+046 6 1.446095E+05 3.802755E+02 6.052273E+01 0.0 0.0

7 7 2.829334E+05 5.319149E+02 8.465688E+01 0.0 0.0

8 8 5.007846E+05 7.076614E+02 1.126278E+02 0.0 0.0

9 9 8.291153E+05 9.105577E+02 1.449198E+02 0.0 0.0

10 10 1.302097E+06 1.141094E+03 1.816108E+02 0.0 0.0

11 11 1.942606E+06 1.393774E+03 2.218260E+02 0.0 0.0

12 12 2.978247E+06 1.725760E+03 2.746632E+02 0.0 0.0

13 13 5.330453E+06 2.308777E+03 3.674533E+02 0.0 0.0

14 14 1.028805E+07 3.207499E+03 5.104893E+02 0.0 0.015 16 2.174905E+07 4.663588E+03 7.422330E+02 0.0 0.0

16 15 3.803833E+07 6.167522E+03 9.815917E+02 0.0 0.0



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(Cont.)Component Modal Synthesis

Assign to the residual structure only the superelement endpoints that are assumed tobe fixed for calculation of component modes.

Specify Q-set (SEQSET1) for each superelement along with the corresponding modalvariables (SPOINT).

Request eigensolution (METHOD) for both superelements and the residual structure.$ FILE = SEDYN3.DAT$

SOL 103TIME 5CENDTITLE = SUPERELEMENT CMS SAMPLE RUN 3SPC = 10$SEALL = ALL $ ONLY REQUIRED IF SOL


93/136



94/136


(Cont.)

GDR and CMR

Modified Case Control from GDR-only file set-up. In addition,eigensolution is requested for both superelements and the residualstructure.

$ FILE = SEDYN4.DAT$SOL 103TIME 5CENDTITLE = SUPERELEMENT CMS SAMPLE RUN 4SEALL = ALL $ ONLY REQUIRED IF SOL


95/136



96/136


(Cont.)

R E A L E I G E N V A L U E SMODE EXTRACTION EIGENVALUE RADIANS CYCLES GENERALIZED GENERALIZED


1 1 6.261534E+03 7.912985E+01 1.259391E+01 1.000000E+00 6.261534E+03

2 2 4.758257E+04 2.181343E+02 3.471715E+01 1.000000E+00 4.758257E+04

3 3 1.829213E+05 4.276930E+02 6.806945E+01 1.000000E+00 1.829213E+05

4 4 5.001845E+05 7.072372E+02 1.125603E+02 1.000000E+00 5.001845E+05

5 5 1.117615E+06 1.057173E+03 1.682543E+02 1.000000E+00 1.117615E+06

6 6 2.185548E+06 1.478360E+03 2.352883E+02 0.0 0.0

SUPERELEMENT CMS SAMPLE RUN 4 JUNE 26, 1990 MSC.NASTRAN 10/ 20/ 89 PAGE 23

SUPERELEMENT 0




1 1 2.004112E+01 4.476730E+00 7.124937E01 1.000000E+00 2.004112E+01

2 2 7.871165E+02 2.805560E+01 4.465187E+00 1.000000E+00 7.871165E+02

3 3 6.171481E+03 7.855878E+01 1.250302E+01 1.000000E+00 6.171481E+03

4 4 2.370327E+04 1.539587E+02 2.450328E+01 1.000000E+00 2.370327E+04

5 5 6.486243E+04 2.546810E+02 4.053374E+01 1.000000E+00 6.486243E+04

6 6 1.447435E+05 3.804517E+02 6.055077E+01 0.0 0.07 7 2.831655E+05 5.321330E+02 8.469160E+01 0.0 0.0

8 8 5.018220E+05 7.083940E+02 1.127444E+02 0.0 0.0

9 9 8.432106E+05 9.182650E+02 1.461464E+02 0.0 0.0

10 10 1.317067E+06 1.147635E+03 1.826518E+02 0.0 0.0

11 11 2.444493E+06 1.563487E+03 2.488367E+02 0.0 0.0

12 12 4.798879E+06 2.190634E+03 3.486503E+02 0.0 0.0

13 14 1.099342E+07 3.315632E+03 5.276993E+02 0.0 0.0

14 13 1.587894E+07 3.984839E+03 6.342068E+02 0.0 0.0

GDR and CMR (Cont.)



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(Cont.)CMS with Free-Free Components

Specify exterior points, which are unconstrained during CMS, with SECSET1entries.

Recommend not using the SESUP entry or calculating 0.0 Hz componentmodes $ FILE = SEDYN5.DAT$

SOL 103TIME 5CENDTITLE = SUPERELEMENT CMS SAMPLE RUN 5

SEALL = ALL $ ONLY REQUIRED IF SOL


98/136


(Cont.)

SUPERELEMENT CMS SAMPLE RUN 5 MAY 2, 1990 MSC.NASTRAN 1/ 4/ 89 PAGE 16

SUPERELEMENT 100




1 1 3.170071E+04 1.780469E+02 2.833705E+01 1.000000E+00 3.170071E+ 04

2 2 2.409813E+05 4.908985E+02 7.812891E+01 1.000000E+00 2.409813E+ 05

3 3 9.273744E+05 9.630028E+02 1.532666E+02 1.000000E+00 9.273744E+ 05

4 6 2.541635E+06 1.594251E+03 2.537329E+02 1.000000E+00 2.541635E+ 06

5 7 5.702000E+06 2.387886E+03 3.800439E+02 1.000000E+00 5.702000E+ 06

6 8 1.121551E+07 3.348956E+03 5.330029E+02 1.000000E+00 1.121551E+ 07

7 9 2.010154E+07 4.483474E+03 7.135671E+02 1.000000E+00 2.010154E+ 07

8 10 3.353399E+07 5.790854E+03 9.216431E+02 1.000000E+00 3.353399E+ 07

SUPERELEMENT CMS SAMPLE RUN 5 MAY 2, 1990 MSC.NASTRAN 1/ 4/ 89 PAGE 19

SUPERELEMENT 200




1 1 6.261533E+03 7.912984E+01 1.259391E+01 1.000000E+00 6.261533E+ 03

2 2 4.758247E+04 2.181341E+02 3.471711E+01 1.000000E+00 4.758247E+ 043 3 1.829191E+05 4.276904E+02 6.806904E+01 1.000000E+00 1.829191E+ 05

4 6 5.001635E+05 7.072224E+02 1.125579E+02 1.000000E+00 5.001635E+ 05

5 7 1.117487E+06 1.057113E+03 1.682447E+02 1.000000E+00 1.117487E+ 06

6 8 2.184376E+06 1.477963E+03 2.352252E+02 1.000000E+00 2.184376E+ 06

7 9 3.883847E+06 1.970748E+03 3.136542E+02 1.000000E+00 3.883847E+ 06

8 10 6.435782E+06 2.536884E+03 4.037577E+02 1.000000E+00 6.435782E+ 06

9 11 1.010135E+07 3.178262E+03 5.058361E+02 1.000000E+00 1.010135E+ 07

10 12 1.518767E+07 3.897136E+03 6.202484E+02 1.000000E+00 1.518767E+ 07

11 13 2.204906E+07 4.695643E+03 7.473347E+02 1.000000E+00 2.204906E+ 07

12 14 3.106928E+07 5.573983E+03 8.871269E+02 1.000000E+00 3.106928E+ 07

CMR with Free-Free Components (Cont.)


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APPENDIX 6ATHE CRAIG-BAMPTON MEDTHOD


100/136


C G O OHAND-SOLVED EXAMPLE

DEFAULT CMS METHOD FIXEDBOUNDARY CMS


101/136


BOUNDARY CMS

Description of Methodology (better known as Craig-Bampton CMS)

The superelement matrices are partitioned into two sets of degreesof freedom (DOFs). The first set (the B-set) represents theboundary points. The second set is the interior DOFs (the O-set).

A set of constraint modes is generated. Each constraint mode

represents the motion of the model resulting from moving one

boundary DOF 1.0 unit, while holding the other boundary DOFfixed. Therefore, there is one constraint mode for each boundary

DOF (these vectors are known as GOATin MSC.NASTRAN)

In matrix form,

(Pbis not actually applied.)

The first line gives

bbb

ob

bbbo

oboo

P

0

IKK

KK

)(G}{ OAT}]{I[K][K bbob1

ooob

DEFAULT CMS METHOD FIXEDBOUNDARY CMS (Cont )


102/136


BOUNDARY CMS (Cont.)giving the following constraint modes:

Now the O-set equations are solved for the fixed-boundary modes(known as GOAQin MSC.NASTRAN).

As many fixed-boundary modes as are desired are found. Then theyare concatenated with the constraint modes to form the generalizedcoordinates.

The mass and stiffness matrices are pre- and postmultiplied by these

modes to obtain the generalized mass and stiffness

where the F-set is the union of the B- and O-sets.

bb

obb

I}{

0}] {[}] {[2

k oooooooo KM

0Ibb

ooobG

}{

}] {[}{][

}] {[}{][

T

T

GffGG

GffGG

MM

KK

DEFAULT CMS METHOD FIXEDBOUNDARY CMS (Cont )


103/136


BOUNDARY CMS (Cont.)

These generalized matrices contain physical DOFs

representing the boundaries and modal coordinates

representing the fixed-boundary component modes.

At this point, these matrices can be treated like any otherstructural matrices, and data recovery can be performed for thecomponent in a manner similar to using modal coordinates. Thatis, the displacements of the generalized coordinates aremultiplied by the associated vectors and added together toobtain the component displacements.

The calculated modes for each superelement are internally

scaled to have a maximum displacement = 1.0 inMSC.NASTRAN (regardless of the scaling requested by theuser).


104/136

SOLUTION BY HAND (Cont.)


105/136


( ) Superelement 1

Mass at Grid Point 3 belongs to the residual structure and is therefore

exterior.

Grid Point 3 is the boundary point; solve for constraint modes.

where

5

4

3

gggg

U

U

U

100

010

000

M

110

121

011

K

0

0

P

U

U

1

110

121

011 b

5

4

21

11K

0

1K

11

12K

1

oo

ob

oo



106/136


( )

where

Solve for fixed-boundary modes.

Note: Internally MSC.NASTRAN uses componentmodes scaled to a maximum deformation of 1.0.Output for the component modes is based on thenormalization performed by the eigenvalue solution.

1

1

11

1

0

1

21

11

b

ob

}{11

12

0

0.0}] {KM[ oo2

2

oooooo

2



107/136


( )

where 1001 and 1002 are scalar points used to represent Superelement 1smodes.

011

12det

2

2

Hz.2575Hz,.098f

2.618,3819.2

3820.103820.

03820.16180.1

3820.6180.10.2

}] {M[}{

u

u

u

6180.300

05279.0

000

}] {K[}{

6180.0.11

0.1618.1

001

6180.0.1

0.16180.

5257.

8506.

6180.

0.1

8506.

5257.

0.1

6180.

Ggg

T

G

1002

1001

3

Ggg

T

G

G

oo

22

11

Normalized tounit mass



108/136


( )

Superelement 2

where 1005 is a scalar point used to represent Superelement2s mode

}1{}{

1,1

000

010

000

110

121

011

oo

MooKoo

MK gggg

2251.f

0.22

01012/12/1

001

}{ G

u

u

u

0.150.50.

50.25.25.

50.25.25.

}] {M[}{

u

u

u

0.200

05.5.

05.5.

}] {K[}{

1005

3

1

GggT

G

1005

3

1

Ggg

T

G

10

2/12/1

01

b



109/136


( )

Residual Structure Before adding superelement:

1005

1002

1001

3

1

gg

gg

U

U

U

U

U

00000

00000

00000

00010

00001

M

00000

00000

00000

00000

00000

K



110/136


( )

Add Superelement 1

00000

03820.103820.0

003820.16180.10

03820.6180.130

00001

M

000000618.3000

005279.00

00000

00000

K

gg

gg



111/136


Add Superelement 2

0.1005.5.

03820.103820.0

003820.16180.10

5.3820.6180.125.325.

5.0025.25.1

M

0.200000618.3000

005279.00

0005.5.

0005.5.

K

gg

gg



112/136


Apply constraints at DOF 1.

Solve which gives

Data recovery (grid point displacement for mode 1)

Residual Structure

1005

1002

1001

3

ffff

U

U

U

U

0.1005.

03820.103820.

003820.16180.1

5.3820.6180.125.3

M

2000

0618.300

005279.0

0005.

K

0}}{MK{ fff2

ff

.5321.3,3473.2,00.1,1206.2

7568.7705.2887.0137.

7012.05464.0986.00572.

8619.3188.0937.12315.

6565.2280.5773.4285.

f

U

U

4285.

0

3

1



113/136


Superelement 2

for exterior points

Superelement 1

for exterior points

1005

3

1

G2

U

U

U

0137.

4285.

0

1002

1001

3

G1

U

U

U

00572.

2315.

4285.

3

2

1

G22G21

u

u

u

4285.

2280.

0

0137.

4285.

0

010

12/12/1

001

}}{{

5

4

3

G11G11

u

u

u

6565.

5773.

4285.

00572.

2315.

4285.

6180.11

16180.1

001

}}{{

SOLUTION USING MSC.NASTRAN SOL103


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103ID CMS1, SAMPLE PROBLEM FOR CMSSOL 103TIME 10CENDTITLE = SAMPLE PROBLEM FOR CMSSPC = 1

SUBCASE 1DISP = ALLLABEL = CMS OF SUPERELEMENTSSET 1000 = 1,2SUPER =1000METHOD=2 $ GET 2 MODESSUBCASE 2LABEL=SOLVE FOR RESIDUAL STRUCTURE MODES IF DESIREDMETHOD = 1DISP = ALLBEGIN BULKPARAM,FIXEDB,1PARAM,GRDPNT,0EIGRL,1,,,10EIGRL,2,,,2$ ADD MODAL COORDINATES FOR S.E. 1SPOINT,1001,THRU,1010SEQSET1,1,0,1001,THRU,1004SEQSET1,2,0,1005,THRU,1010GRID,1,,0.,0.,0.=,(1),=,(10.),===(3)CELAS2,1,1.,1,1,2,1CELAS2,2,1.,2,1,3,1CELAS2,3,1.,3,1,4,1CELAS2,4,1.,4,1,5,1$ DEFINE SUPERELEMENTS

SESET,1,4,5SESET,2,2PARAM,AUTOSPC,YESSPC1,1,123456,1CONM2,11,1,,1.CONM2,12,2,,1.CONM2,13,3,,1.CONM2,14,4,,1.CONM2,15,5,,1.ENDDATA

The input data was run inMSC.NASTRAN:

SELECTED OUTPUT FROMMSC NASTRAN


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MSC.NASTRANSAMPLE PROBLEM FOR CMS OCTOBER 3, 1989 MSC.NASTRAN 1/ 4/ 89 PAGE 18

SUPERELEMENT 1




1 1 3.819660E01 6.180340E01 9.836316E02 1.000000E+00 3.819660E01

2 2 2.618034E+00 1.618034E+00 2.575181E01 1.000000E+00 2.618034E+00

SUPERELEMENT 2




1 1 2.000000E+00 1.414214E+00 2.250791E01 1.000000E+00 2.000000E+00

SUPERELEMENT 0R E A L E I G E N V A L U E S



1 1 1.206148E01 3.472964E01 5.527393E02 1.000000E+00 1.206148E01

2 2 1.000000E+00 1.000000E+00 1.591549E01 1.000000E+00 1.000000E+00

3 4 2.347296E+00 1.532089E+00 2.438395E01 1.000000E+00 2.347296E+00

4 3 3.532089E+00 1.879385E+00 2.991135E01 1.000000E+00 3.532089E+00

SUPERELEMENT 0

SOLVE FOR RESIDUAL STRUCTURE MODES IF DESIRED SUBCASE 2

EIGENVALUE = 1.206148E01

CYCLES = 5.527393E02 R E A L E I G E N V E C T O R N O . 1

POINT ID. TYPE T1 T2 T3 R1 R2 R3

1 G 0.0 0.0 0.0 0.0 0.0 0.0

3 G 4.285251E01 0.0 0.0 0.0 0.0 0.0

1001 S 2.315487E01 5.720218E03 0.0 0.0 1.375089E02 0.0

1007 S 0.0 0.0 0.0 0.0

SELECTED OUTPUT FROMMSC NASTRAN (Cont )


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MSC.NASTRAN (Cont.)

SAMPLE PROBLEM FOR CMS OCTOBER 3, 1989 MSC.NASTRAN 1/ 4/ 89 PAGE 43

SUPERELEMENT 1CMS OF SUPERELEMENT 1 SUBCASE 1

EIGENVALUE = 2.347296E+ 00



3 G 2.280134E01 0.0 0.0 0.0 0.0 0.0

4 G 5.773503E01 0.0 0.0 0.0 0.0 0.0

5 G 4.285251E01 0.0 0.0 0.0 0.0 0.0

1001 S 3.188475E01 5.463955E01 0.0 0.0

SAMPLE PROBLEM FOR CMS OCTOBER 3, 1989 MSC.NASTRAN 1/ 4/ 89 PAGE 48

SUPERELEMENT 2

CMS OF SUPERELEMENT 1 SUBCASE 1

EIGENVALUE = 1.206148E01



1 G 0.0 0.0 0.0 0.0 0.0 0.0

2 G 2.280134E01 0.0 0.0 0.0 0.0 0.0

3 G 4.285251E01 0.0 0.0 0.0 0.0 0.0

1005 S 1.375089E02 0.0 0.0 0.0 0.0 0.0

EXTERNAL SUPERELEMENTS


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In V70, the ability to use external superelements, complete withdata recovery was added for SOLs 101 and 103.

In V70.5, these new external superelements have beenextended into SOLs 101 thru 159 and data recovery for them

exists in SOLs 101, 103, and 107 thru 112.

The procedure for this is as follows:

Create reduced model.

Read in reduced model as an external superelement.

Perform solution and data recovery of assembly.

Perform data recovery on external superelement.

CREATING AN EXTERNALSUPERELEMENT


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SUPERELEMENT A separate model file is used to create an external

superelement. The component must be modeled as the residual structure in

this file. upstream superelements are allowed in this file, but the residual structure

(assembly) is the component with reduced matrices will be available for asan external superelement in subsequent runs.

Interface dof must be identified using ASETi, BSETi, and/orCSETi entries.

If you are using component modal synthesis, QSETi dof must beprovided to represent the component modes.

Only one boundary condition may be used.

Only one SUBCASE is required. If you are performing a static solution, multiple residual structure

SUBCASEs may be specified, but they must be in the correct order for usewhen the component is attached.

CREATING AN EXTERNALSUPERLEMENT (Cont)


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SUPERLEMENT (Cont)

There are 4 ways the reduced data may be stored for

use in future runs.

The format of the reduced data is controlled byPARAM,EXTOUT: MATRIXDB = the reduced matrices are stored on the database.

They do not contain connectivity data. DMIGDB = the reduced matrices are stored on the database using

DMIG format and can be automatically attached.

DMIGOP2 = the reduced matrices are written using OUTPUT2format to a file (specified by PARAM,EXTUNITdefault=30). Thematrices are stored using DMIG format.

DMIGPCH = the reduced matrices are written to the .pch file

using DMIG format.


120/136

ATTACHING AN EXTERNALSUPERELEMENT (Cont)


121/136


SUPERELEMENT (Cont) If EXTOUT was DMIGPCH, include the .pch file from the previous run and use the following case

control for the superelement:

K2GG= KAAXP2G = PAX

M2GG = MAAX

B2GG = BAAx

At this point, the run will proceed normally, attaching the external superelementand solving the problem.

Standard data recovery is available for all superelements (except the external

ones) during the solution run.

Data recovery for the external superelement run requires saving the databasefrom the assembly run and performing a data recovery restart on the externalsuperelement. This is controlled by PARAM,EXTDROUT:

EXTDROUT=MATRIXDBsolution for boundary displacements stored in database using thesequencing of the assembly model

EXTDROUT = DMIGDBsolution stored in database using DMIG (only applicable if EXTOUT was

set to DMIGDB or DMIGOP2)

EXTDROUT = DMIGOP2writes DMIG to OUTPUT2 file selected by PARAM,EXTDRUNT (default =unit 31)available only for EXTOUT=DMIGOP2 or DMIGDB

DATA RECOVERY FOR AN EXTERNALSUPERELEMENT


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SUPERELEMENT

Performing data recovery on the externalsuperelement requires using a restart from the runwhich created the reduced matrices.

The run requires the following FMS (or similar): ASSIGN SE10=run1.MASTER

RESTART, LOGICAL=SE10 $ readonly restartnot required

ASSIGN RESID=run2.MASTER

DBLOCATE DATABLK=(EXTDB), LOGICAL=RESID

The run also requires PARAM,EXTDR,YES


123/136

ATTACHING AN EXTERNALSUPERELEMENT (Cont)


124/136


SUPERELEMENT (Cont)

Remarks:1. EXTRN can only be specified in partitioned Bulk Data Sections and

is ignored in the main Bulk Data Section.

2. Connection grids must be specified in the partitioned Bulk DataSection following BEGIN SUPER = SEID.

3. THRU may be specified in fields 3, 5, or 7.

4. Pairs of blank fields may be entered to allow easier modification ofthe EXTRN entry.

SAMPLE PROBLEM


125/136


The solution will be a modal transient, SOL 112.

The loading on this model is a pressure on the elements in Superelement 10(the external superelement).

The solution will consist of 5 runs and will use the MATRIXDB method (theother approaches would also work fine). Run1process SE 10

Run 2Read in SE 10 as external

Run3define and process internal SE 11

Run 4Define and solve residual structure

Run 5data recovery on external SE 10

SAMPLE PROBLEM USING MATRIXDBf


126/136


SOL 112 $ superelement SSS modal transientCENDTITLE = Generate data to be attached as SE 10PARAM,EXTOUT,MATRIXDB

SUBCASE 1loadset = 15 $ Define loadingMETHOD = 10 $ request cmsparam,resvec,yes $ request residual vectorsSPC = 1BEGIN BULK$ define loads$lseq,15,1001,101lseq,15,2001,201pload2,101,1.,97,thru,112force,201,1108,,1.,10.,0.,0.$$ define modal coordinates for CMS$SPOINT 91001 THRU 91006

QSET1 0 91001 THRU 91006$$ define which dofs will be retained (i.e. which dofs will form the$ attachment to the system model when we bring it in as an external se)$

ASET1 123456 1100 THRU 1104

$$ print dof map for connecting the external superelement to the$ system model, in se10.dat, with EXTRN entry. The MATRIXDB option$ requires the dofs specified in the subsequent se10.dat run be in$ ASET ascending order. This is obtained with these parameters in$ the f06$ usetsel =128 will print only ASET dof$

PARAM USETPRT 0PARAM USETSEL 128

$EIGRL 10 4

PSHELL 1 1 .01 1 1CQUAD4 97 1 1100 1101 1106 1105$$ model description occurs here...$GRID 1122 5.5 3. 0.GRID 1123 5.75 3. 0.GRID 1124 6. 3. 0.ENDDATA

Run1file run1_se10.dat

SAMPLE PROBLEM USING MATRIXDB(Cont)


127/136


( )ASSIGN SE10DB = run1_se10.MASTER

DBLOCATE DB=(EXTDB), CONVERT(SEID=10), LOGI=SE10DB$SOL 103TIME 600CENDTITLE = Add external data and call it SE 10SET 99 = 10SEALL = 99 $ process only SE 10SUBCASE 1SUPER = 10 $ process only SE 10param,resvec,yesloadset=15METHOD = 10BEGIN BULK$ declare SE 10 as external$SEBULK 10 EXTERNAL

BEGIN SUPER = 10$$ set flag for data recovery$PARAM EXTDROUTMATRIXDB$ dynamic loading definitionlseq,15,1001,101lseq,15,2001,201$pload2,101,1.,97,thru,112$force,201,1108,,1.,10.,0.,0.SPOINT 10001 THRU 10006QSET1 0 10001 THRU 10006

ASET1 123456 1030 THRU 1034

$

$ Connect external superelement to the system model:$ Note that for the MATRIXDB option the order of the$ grids must be in ASET ASCENDING order$EXTRN 1030 123456 1031 123456 1032 123456 1033 123456

1034 123456 10001 0 10002 0 10003 010004 0EIGRL 10 4GRID 1030 5. 2. 0.GRID 1031 5.25 2. 0.GRID 1032 5.5 2. 0.GRID 1033 5.75 2. 0.GRID 1034 6. 2. 0.ENDDATA

Run2filerun2_se10ln.datread

SE 10 as external



128/136


( )ASSIGN MASTER=run2_se10in.MASTERRESTART, VERSION=1, KEEP

SOL 112TIME 600CENDTITLE = Add in SE 11ECHO = NONEMAXLINES = 999999999SET 99 = 10,11SEALL = 99SUBCASE 1SUPER = 10METHOD = 10param,resvec,yesloadset = 15SUBCASE 2

SUPER = 11 $ process only SE 11

METHOD = 11

param,resvec,yes

loadset = 15BEGIN BULKBEGIN SUPER = 11

$$ dynamic loading definitionlseq,15,1001,101lseq,15,2001,201$ define nonexistant loads to allow upstream loads$ as place holdersforce,101,1007,,0.,1.,0.,0.force,201,1007,,0.,1.,0.,0.$ define modal coordinates for CMS$SPOINT 11001 THRU 11006

QSET1 0 11001 THRU 11006$$ define attachment points to the next SE $ optional if they already exist in the model$ASET1 123456 1000 THRU 1004

$EIGRL 11 4

PSHELL 1 1 .01 1 1CQUAD4 81 1 1000 1001 1006 1005$ model of SE 11......GRID 1023 5.75 2. 0.GRID 1024 6. 2. 0.ENDDATA

Run3file run2_se11.dat

define and process SE11



129/136


( )ASSIGN MASTER=run2_se10in.MASTERRESTART, VERSION=2, KEEPSOL 112

TIME 600$$ insert dmap avoidance for error 32074 see next page$CENDTITLE = Solve residual structureSUBCASE 1SUPER = 10METHOD = 10loadset = 15param,extdrout,matrixdbSUBCASE 2SUPER = 11METHOD = 11loadset = 15SUBCASE 3SUPER = 0 $ process only the residual

METHOD = 90tstep = 35SPC = 1loadset = 15

dload = 25SPCFORCES(plot)=ALLBEGIN BULK$tstep,35,100,.01tload2,25,1001,,,0.,100.,10.,90.

lseq,15,1001,101lseq,15,2001,201force,101,1,,0.,1.,0.,0.force,201,1,,0.,1.,0.,0.$EIGRL 90 4SPC1 1 123456 1 18 35 52 69PSHELL 1 1 .01 1 1CQUAD4 1 1 1 2 19 18CQUAD4 2 1 2 3 20 19GRID 104 5.75 1. 0.GRID 105 6. 1. 0.ENDDATA

Run4file run4_resid.datdefine residual structure and solve



130/136


( )

ASSIGN EXT10=run1_se10.MASTER

RESTART, LOGI=EXT10

$

ASSIGN SYSTEM=run2_se10in.MASTER

DBLOCATE DB=(EXTDB), WHERE(SEID=10),

LOGI=SYSTEM

$

SOL 112

TIME 600

diag 56

CEND

TITLE = Data Recovery for external data

ECHO = NONE

MAXLINES = 999999999

$

$ tell NASTRAN this is a data recovery run for the external data

$

PARAM,EXTDR,YES

$

DISP = ALL

SUBCASE 1

METHOD = 10

param,resvec,yes

loadset = 15

tstep = 35

dload = 25

SPCFORCES(plot)=ALL

$

BEGIN BULK

ENDDATA

Run5file run5_dr10.datperform data recovery on se 10



131/136


( )

Plot of displacement GRID 1020

SAMPLE PROBLEM USING DMGIOP2PROGRAM

assign file for use by dmigop2


132/136


$

assign output2=ext10.op2, unit=30, delete

$

SOL 112 $ superelement SSS modal transient

$ include alter for OTM optional

include alteria.v705

CENDTITLE = Generate data to be attached as SE 10

$

param,extout,dmigop2

$

SUBCASE 1

loadset = 15

METHOD = 10

param,resvec,yes $ request residual vectors

SPC = 1

disp = all

stress = all

force = all

BEGIN BULK$

$ parameter to create OTM using alter1ia.v705

param,drmh,yes

$

$ define loadings used for residual vectors (also stored in database)

lseq,15,1001,101

lseq,15,2001,201

pload2,101,1.,97,thru,112

force,201,1108,,1.,10.,0.,0.

$

$ define modal coordinates for CMS allow for 6 modes

$

SPOINT 91001 THRU 91006QSET1 0 91001 THRU 91006

$

$ define which dofs will be retained (i.e. which dofs will form the

$ attachment to the system model when we create SE10 in se10.dat)

$

ASET1 123456 1100 THRU 1104

$

EIGRL 10 4

$ model goes here....

$

ENDDATA$

Run 1 + file run1`_se.dat

SAMPLE PROBLEM USING DMGIOP2$ run 2 se10.dat locate external data and attach as


133/136


$ superelement 10$ $ attach file containing reduced matrices and OTMASSIGN inputt2=ext10.op2, unit=30$SOL 103

diag 8,15,56include alteria.v705CENDTITLE = Add external data and call it SE 10SET 99 = 10SEALL = 99SUBCASE 1SUPER = 10 $ process only SE 10param,resvec,yesloadset=15METHOD = 10BEGIN BULK$ declare SE 10 as externalSEBULK 10 EXTERNAL

BEGIN SUPER = 10$ point to file used for INPUTT2

param,extunit,30$ set flag for data recoveryPARAM EXTDROUTDMIGOP2

param,extdrunt,31$ dynamic loading definitionlseq,15,1001,101lseq,15,2001,201$pload2,101,1.,97,thru,112$force,201,1108,,1.,10.,0.,0.EXTRN 1100 123456 1101 123456 1102 123456 1103 1234561104 123456 91001 0 91002 0 91003 091004 0 91005 0 91006 0$ identify exterior points (not needed if coincident points elsewhereASET1 123456 1100 THRU 1104$ define modal coordinates for CMSSPOINT 91001 THRU 91006QSET1 0 91001 THRU 91006GRID 1100 5. 2. 0.GRID 1101 5.25 2. 0.GRID 1102 5.5 2. 0.GRID 1103 5.75 2. 0.GRID 1104 6. 2. 0.ENDDATA

Run2file run2_se10in.dat

SAMPLE PROBLEM USING DMGIOP2$ SE 10 is all ready in the run2 se10in DBALL database


134/136


$ SE 10 is all ready in the run2_se10in.DBALL database$$RESTART LOGI=SE10M

ASSIGN MASTER=run2_se10in.MASTERRESTART, VERSION=1, KEEP

SOL 112TIME 600include alteria.v705CENDTITLE = Add in SE 11SET 99 = 10,11SEALL = 99SUBCASE 1SUPER = 10METHOD = 10param,resvec,yes

loadset = 15$ add new subcase (let the autorestart logic work it out)

SUBCASE 2SUPER = 11 $ process only SE 11METHOD = 11param,resvec,yes

loadset = 15BEGIN BULKBEGIN SUPER = 11lseq,15,1001,101lseq,15,2001,201$ define nonexistant loads to allow upstream loads$ as place holdersforce,101,1007,,0.,1.,0.,0.

force,201,1007,,0.,1.,0.,0.$ define modal coordinates for CMSSPOINT 11001 THRU 11006QSET1 0 11001 THRU 11006$$ attachment points to the next SE not needed if coincident points exist$ASET1 123456 1000 THRU 1004$EIGRL 11 4$ model of se 11ENDDATA

Run3file run3 se11.dat

SAMPLE PROBLEM USING DMGIOP2$ 4 id d dd id l d d l


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$ run4_resid.dat add residual data and solve$ assign file for boundary solution$assign output2=se10bndry.op2, unit=31, delete$$ SE 10 and 11 are in the run2_se10 database.

$ for a readonly restart (not required)assign oldrun=run2_se10in.MASTERrestart, logical=oldrun

$SOL 112TIME 600include alteria.

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Lec 07 Superelement NAS105