Modal Harmonic Ex

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Course in ANSYS

Example0410

Example0410 2

Example – Frame 2D

E = 200E9N/m2

= 0.3

L = 2m

H = 3m

I = 0.14/12m4

r = 7860kg/m3

Objective:

Compute the harmonic responseTasks:

Perform a modal analysis

Display the mode shapes

Perform a harmonic analysis

Topics:Topics: Start of analysis, Element type,

Real constants, Material, modeling, ele-

ment size for beam models, modal and

harmonic analysis


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Example0410 3

Example - title

Utilit y Menu > File > Change Title

/title, Frame 2D

Utility Menu > File > Change Jobname

/jobname, Example0410

Enter: Frame 2D

Command line entryGUI

Enter: Example0410

Example0410 4

Example - Parameters


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Example0410 5

Example - KeypointsPreprocessor > Modeling > Create > Keypoints > In Active CS/PREP7

K,,,,

K,,,3,

K,,2,3,

Note: An empty boxresult in a zero. It is

allowed to enter 0.0in each box.

Enter 0,0,0 and

Press Apply

Enter 0,3,0 and

Press Apply

Enter 2,3,0 andPress Apply

General format:

K,#,X,Y,Z

# Keypoint number X Keypoint x-coordinateY Keypoint y-coordinateZ Keypoint z-coordinate

Note: An empty #result in automaticnumbering.

Example0410 6

Example - NumberingUtility Menu > PlotCtrls > Numbering Switch on Keypoint numbers

Press OK


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Example0410 7

Example - LinesPreprocessor > Modeling > Create > Lines > Lines > Straight LineCreate a line between KP1 and KP2 and KP2 and KP3.

L,1,2

L,2,3 HINT: By clicking with the right-

hand mouse button you shift

between the Pick/Unpick

function. This is indicated by

the direction of the cursor

arrow:

Pick: upward arrow

Unpick: downward arrow

Press OK or Cancel

to finish selection

Example0410 8

Example - Plot - Nodes

Plot Keypoints and Lines


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Example0410 9

Example – Element TypePreprocessor > Element Type > Add/Edit/Delete

Press Add

Example0410 10

Example - Element TypePreprocessor > Element Type > Add/Edit/Delete

Press Options

Press Help to learn more about the

element.


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Example0410 11

Example – Real ConstantsPreprocessor > Real Constants > Add

Place the cursor

on the relevant

element and

press OK

Example0410 12

Example - Real ConstantsPreprocessor > Real Constants > Add

Press OK

Press Close

to finish

Enter cross

sectional data


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Example0410 13

Example - Material PropertiesPreprocessor > Material Props > Material ModelsDouble Click

to step in the

material tree

Example0410 14

Example - Material PropertiesPreprocessor > Material Props > Material Models

Enter E

Modulus of elasticity

Enter nu

Poisson’s ratio

Click here

to Close

Press OK


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Example0410 15

Example - DensityEnter 7830

Press OK

Example0410 16

Example - MeshingPreprocessor > Meshing > Size Cntrls > ManualSize > Lines > Picked Lines

Select/PickL1

Press OK when finish with selection Enter 30


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Example0410 17

Example - MeshingPreprocessor > Meshing > Size Cntrls > ManualSize > Lines > Picked Lines

Select/PickL2

Press OK when finish with selection Enter 20

Example0410 18

Example - MeshingPreprocessor > Meshing > Mesh > Lines

Select individual lines to be meshed by Picking

Select all lines defined to be meshed

NB: It is often necessary to “Clear” the model for

example if Element Type is to be changed


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Example0410 19

Example – Analysis Type

Solution > Analysis Type > New Analysis

File > Write DB log file

Enter “example0410.lgw”

Press OK

Example0410 20

Example – MA Analysis Options

Select

Block

Lanczos

Enter 10

Enter 10

Switch

to Yes

Press OK


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Example0410 21

Example – MA Analysis Options

Press OK

Example0410 22

Example – Define LoadsSolution > Define Loads > Apply > Structural > Displacement > On Keypoints

Select keypoint 1

Press OK

Select UX and UY equal zero


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Example0410 23

Example – Define LoadsSolution > Define Loads > Apply > Structural > Displacement > On KeypointsSelect keypoint 2

Press OK

Select UY equal zero

Example0410 24

Example - Damping

Enter 0.02 for Constant damping ratio

Press OK


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Example0410 25

Example - SolveSolution > Solve > Current LS

Press OK

Example0410 26

Example - SolvePress Close

Press here

to Close


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Example0410 27

Example - PostProcessingGeneral Postproc > Plot Results > Deformed Shape

Select “Def+undeformed”

and Press OK

Example0410 28

Example – Results Summary


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Example0410 29

Example – Read ResultsGeneral Postproc > Plot Results > Deformed Shape

Select “Def+undeformed”

and Press OK

Read first set

Example0410 30

Example – Mode 1


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Example0410 31

Example – Result viewer

Select mode shape, the last

mode read is displayed

Press OK

Example0410 32

Example – Result viewer Select DOF

solution and

Def+undeformed

Press OK and animation is controlled

by the following dialog


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Example0410 33

Example – Read Results

Enter 3 and compare with CookPress OK

Example0410 34

Example - List

SelectPress OK


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Example0410 35

Example - List

Compare result with Cook

Example0410 36

Example – Analysis Type

Solution > Analysis Type > New Analysis

File > Write DB log file

Enter “example0410.lgw”

Press OK


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Example0410 37

Example – HRA Analysis Options

Select Full

Select

Amplitud+

phase

Press OK

Example0410 38

Example – Define LoadsSolution > Define Loads > Apply > Structural > Force/Moment > On Keypoints

Change to FX

Select keypoint 3

Enter 3000Press OK to finish


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Example0410 39

Example - Freq and SubstpsEnter 50

Enter 160

Enter 110

Select Stepped

Example0410 40

Example - Damping

Enter 0.02 for Constant damping ratio

Press OK


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Example0410 41

Example - SolveSolution > Solve > Current LS

Press OK

Example0410 42

Example - SolvePress Close


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Example0410 43

Example – TimeHistory Postpro

Close this dialog box

Example0410 44

Example – Define Variables

Press Add


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Example0410 45

Example – Add Time-History Var.

Press OK

Select Nodal

DOF result

Enter 17

Press OK

Select DOF solution

and Translation UX

Press OK

Example0410 46

Example – Graph Variables

Enter 2 to plot

UX for node 17

Press OK


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Example0410 47

Example – Graph Variables

Documents

Modal Harmonic Ex