Dynaform eta post 1 8 1 application manual

Read result file d3plot into eta/POST As illustrated in Figure 1, click PostProcess on the main menu of eta/DYNAFORM to start eta/POST.. Figure 4 PostProcess Tool Bar Note: If the mult

eta/POST Application Manual

Version 1.8.1

Engineering Technology Associates, Inc

1133 E Maple Road, Suite 200

Troy, MI 48083

Tel: +1 (248) 729 3010

Fax: +1 (248) 729 3020

Email: support@eta.com

of the respective owners

FOREWORD

FOREWORD

The concepts, methods, and examples presented in this text are for illustrative and educational

purposes only, and are not intended to be exhaustive or to apply to any particular engineering problem

or design

This material is a compilation of data and figures from many sources

Engineering Technology Associates, Inc assumes no liability or responsibility to any person or

company for direct or indirect damages resulting from the use of any information contained herein

OVERVIEW

eta/POST is a powerful visualization tool developed by ETA for quick interpretation and estimation

of the LS-DYNA analysis result It provides contour plot, vector plot, deformation plot, FLD, stress distribution, animation, and plot animation for the user to analyze calculation results quickly and accurately It also provides graph for the user to view the time history curve in the LS-DYNA analysis result, and a wide range of tools to convert and interpret simulation analysis result For example, the operations of display setup (label, color, etc.), the advanced curve filtering technology (FIR, SAE, Butterworth, Averaging, etc.), and the calculation of different results

Documentation is also very important for various analyses Eta/POST provides direct and high quality print of graph and plotting function It can export graph to another program with a simple copy command For example, it can easily export a picture to a commonly used word processing program such as MICROSOFT WORD, MICROSOFT POWERPOINT, ADOBE FRAMEMARKER, etc It can also export to EXCEL, database, and desktop printing software, as well as drawing and illustration programs It helps the user to quickly create and publish an integrated report and presentation In addition, eta/POST supports AVI and GIF files, and can include animation presentations in POWERPOINT or WORD documents It supports an exporting E3D file which can play in a free 3D CAE analysis result player eta/3DPlayer developed by ETA, or

be imported to eta/POST directly to play Eta/POST also supports graphic files in TIFF and JPEG formats, which means the user can view the analysis model and result using a standard browser

INTRODUCTION

INTRODUCTION

Welcome to the eta/POST 1.8.1 Application Manual The user interface and operation of eta/POST 1.8.1 are unified on UNIX, Linux, and Windows platforms Therefore, this application manual is available for all platforms except there is a little difference in figures and interface styles This manual

is mainly about the assessment of stamping simulation analysis result in PostProcess, the basic process

of finite element modeling and PostProcess The technical details about finite element simulation, the finite element modeling of PreProcess, and other applications are not included in this manual The user may participate in eta/DYNAFORM advanced training to learn more technical details if necessary This manual uses a fender as a case to explain how to analyze stamping simulation by using eta/POST

A fender is part of vehicle cover panel, and its main defects during the forming process include tearing, thinning, skid marks on the binder ring, wrinkling, springback, etc Therefore, we analyze the formability of the fender in PostProcess through FLD, Thinning, Edge movement, Major strain, Minor strain, Skid mark, Springback, Face Reflection, and Stoning

In addition, the binder hold and forming force are unknown at the beginning of practical production

We can control the binder ring with appropriate velocity in the PreProcess setup, and obtain a predicted value of the binder hold by using Tonnage Prediction in PostProcess after the simulation calculation On this basis, we have a safety coefficient as reference for the selection of stamping equipments The predicted value of forming force can be obtained by reading in relevant LS-DYNA analysis result files through Graph

Note: This manual is available for eta/POST on all platforms Due to different software and hardware environments of different operating systems and different software versions, the figures and descriptions in the manual may have few differences with the specific user interface These differences will be neglected in the manual

TABLE OF CONTENTS

VEHICLE FENDER ··· 1

Read result file d3plot into eta/POST ··· 2

Deformation ··· 3

FLD ··· 6

Thinning ··· 10

Major Strain ··· 13

Minor Strain ··· 14

Edge Movement ··· 15

Skid Mark ··· 16

Tonnage Prediction ··· 18

Spring Back ··· 21

Face Reflection ··· 28

Stoning ··· 30

Graph ··· 32

Output Animation File and Graphics File ··· 34

Output AVI File ··· 35

Output E3D File ··· 36

Output Graphics File ··· 38

SUMMARY ··· 39

ANALYSIS

VEHICLE FENDER

PostProcess Analysis with eta/POST

eta/POST can read in and process all of the useful data in the d3plot file Besides the undeformed model data, the d3plot file contains all of the result files (stain, stress, time history curve, etc.) generated by LS-DYNA eta/POST can plot deformation, FLD, and thinning and distribution of physics quantity, such as stress/strain on blank It can also record this changing process to AVI movie files, and E3d files

Read result file d3plot into eta/POST

As illustrated in Figure 1, click PostProcess on the main menu of eta/DYNAFORM to start eta/POST The default installation path of eta/POST is C:\Program Files\ETA\Dynaform5.9.2 It can also be started by double clicking EtaPostProcessor.exe under this directory,or started by the Dynaform5.9.2 program group from the start menu of the operating system The PostProcess interface is illustrated in Figure 2

Figure 1 PostProcess Menu

ANALYSIS

Figure 3 Open dialog box

2 Select result files of LS-DYNA and files in d3plot, d3drlf, and dynain formats from the file list The d3plot is the result file of forming simulation, including the simulation results of drawing, binder, flanging, and springback process The d3drlf is the result file of gravity simulation The dynain file is the result file of blank deformation, which is used for multiple stages

3 Browse the content for saving result files Select the correct file format and select d3plot file Click the Open button to read in d3plot file The program will automatically pop up the

PostProcess tool bar illustrated in Figure 4 for the user to perform PostProcess operations for result calculation

Figure 4 PostProcess Tool Bar

Note: If the multiple stage result file is opened, the user has to select ETA Multiple stage file in idx format from the file type list

Deformation

The default simulation status is Deformation when the result file is opened Click the Play button to

show the deformation process using animation, as illustrated in Figure 5 The user can move the

Frames/Second slider, and set the desired animation velocity Click the Stop button to stop

animation

Sometimes, it is more convenient to show the plot result of single frames than the whole animation

Select Single Frame in the pull-down menu of Frames, then view the result with single frame, or move the slider under Frame Number to select single frame

Figure 5 Deform Operation

1 In order to view the blank deformation, the user can click ApplicationShow Blank Part

Only to open the blank part only, or select button from the tool bar

2 In the part operation dialog box, close all of the tool parts and keep only the blank part The color

of all the closed parts turns to white, as illustrated in Figure 6 Click Exit to exit the operation

ANALYSIS

Figure 6 Open/Close Part window

3 The user can also use view operation to change views The view operation is the same as the PreProcess, as illustrated in Figure 7 We choose X-Y View here, and the deformed part is

illustrated in Figure 8

Figure 7 View Operation Tool

Figure 8 Deformation

FLD

FLD is utilized to estimate the formability of blank

1 Click button in tool bar

2 The default is MIDDLE in the pull-down menu of Current Component, which indicates that it is the FLD of middle layer The user can also select the TOP or BOTTOM layer according to the requirements, as illustrated in Figure 9 We use the default option here

ANALYSIS

Figure 9 FLD Operation window

3 Click the FLD Curve Option button to set FLD parameters (e.g n, t, r) as illustrated in Figure

10 In order to obtain the accurate FLD of drawing result, we need to make sure that the position and shape of FLC is consistent with the practice before display The FLC can be achieved through two methods The user can define mechanical properties of materials such as the

hardening exponent (n), anisotropy coefficient (r) and sheet thickness (t) These parameters have already been set in PreProcessing The eta/POST will automatically obtain these parameters from the result file The user can also import curve directly to confirm the FLC Keeler’s formula is used here for the default FLD equation In addition, the user can select any color from Curve Filter by using their mouse cursor, and edit the color in the displayed Choose Color dialog box illustrated in Figure 11

Figure 10 FLD Curve Option dialog box

ANALYSIS

Figure 11 Edit Curve Filter Color

4 Select the Edit FLD Window button to define the position of FLD plot window

5 Click the Play button to play the animation of FLD

6 Click the Stop button to stop animation

7 Select the last frame in the single frame state, as illustrated in Figure 12

Figure 12 Fender FLD

As shown in the above figure, it can be seen that there is tearing in the area circled by a red line, and wrinkling in the edge flange area The wrinkling area is not in the interior of the part, which will not influence the use of the part, the majority portion of the part is in the safe area This indicates that the formability of this part is good

Note: The default FLD equation of eta/POST uses Keeler’s formula which is derived from steel

Therefore, if the blank material is aluminum or other materials during the drawing process, the user needs to provide the FLC curve Then the user can import the FLC curve through the curve importing method Refer to Section FLD in the eta/POST Manual for a detailed description of FLC import

Thinning

Thinning is utilized to estimate the forming quality through change of thickness

1 Click button in tool bar

2 Select THINNING in the pull-down menu of Current Component

3 Click the Contour Setting button and set the Contour Level, the minimum and maximum values

of Contour Range to 10, 3, and 25 respectively While clicking the Apply button, the

corresponding color will display behind the input fields for MAX and MIN values The user can click the color to edit, as illustrated in Figure 13

4 Before exiting the Contour Bar Options dialog box, the user can click any color block of the graphic area color bar by using their mouse cursor, and edit the color according to their choice, as

illustrated in Figure 14 Then export for use the next time by selecting ApplicationExport

Color bar Setting

Figure 13 Contour Bar Options window

ANALYSIS

Figure 14 Edit Contour Color

5 Select Single Frame as the frame type and select the last frame

6 Click List Value button to pop up a dialog box illustrated in Figure 15

7 Before exiting the List Value dialog box, open the OptionApply Mouse Tracking option and

move the mouse cursor on the screen At the position where the cursor is placed, the node or element number as well as its thinning ratio of this position will be displayed in real time in the status bar below, as illustrated in Figure 16 Then click the left mouse button to show the specific thinning ratio of the selected node or element on the screen, as illustrated in Figure 17

Figure 15 List Value Option window

Figure 16 Display Node and its Thinning Ratio in Real Time

Figure 17 Thinning Distribution

8 Click List Value Option button to modify the font size and the number of decimal for the

thinning value of select nodes or elements Select List Font 14, and Number of Decimal 2

ANALYSIS

Figure 18 Display node value by table

Normally, the lower limit of thinning ratio for a vehicle cover panel is 0, and the maximum value is calculated according to the material The thinning ratio for the forming portion of vehicle fender within the range of 3% to 25% is accepted here If the thinning ratio is below this range, the stiffness

of the part will be weakened, which may cause tearing As shown in the above figure, the thinning ratios for the forming portion are basically within the acceptable range

Note: The values represented by color in the Thinning figure are expressed in percentage (%) form

Major Strain

Major Strain is utilized to estimate the forming quality of parts

1 Click button in the tool bar

2 Select Single Frame as the frame type and select the last frame

3 Select the List Value button and show the major strain value by selection of mouse cursor, as

illustrated in Figure 19

4 The user can also click the Play button to animate the changing process of major strain

Figure 19 Major Strain

For the cover panel, major strain is used to estimate the forming quality of parts If the major strain has a non-uniform change, the smooth after spray-paint will be influenced As shown in the above figure, the surface quality of the cover panel conforms to the requirements

Minor Strain

Minor Strain is also utilized to estimate the forming quality of parts

1 Click button in the tool bar

2 Select Single Frame as the frame type and select the last frame

3 Select the List Value button, and show the minor strain value by selection of the mouse cursor, as illustrated in Figure 20

4 The user can also click the Play button to animate the changing process of minor strain

ANALYSIS

Figure 20 Minor Strain

For the cover panel, minor strain is used to estimate the forming quality of parts If minor strain has a non-uniform change, the smooth after spray-paint will be influenced As shown in the above figure, the surface quality of the cover panel conforms to the requirements

Edge Movement

Edge Movement is utilized to estimate the blank movement from each direction

1 Click button in the tool bar

2 Select Single Frame as the frame type and select the last frame The edge movement distribution

is illustrated in Figure 21

3 Cancel the Show Flow option and select Show Nearest Distance option Then click the List

ValueList Value Option

4 The user can also show the edge movement of the part by mouse selection, as illustrated in Figure

22

5 The user can also click the Play button to animate the changing process of the edge movement

Figure 21 Edge Movement Distribution

Figure 22 Show Edge Movement

As shown in the above figure, the edge movement of the vehicle fender is uniform

Skid Mark