INTRODUCTION

eta/DYNAFORM Version 5.6 software is an LS-DYNA-based sheet metal forming simulation solution package developed by Engineering Technology Associates, Inc. The specialty CAE software combines the analysis power of LS-DYNA Versions 971 with the streamlined pre- and post-processor functions. These analysis codes and interactive functions are uniquely integrated to service the sheet metal forming industry in tooling design and development. The program also maximizes traditional CAE techniques to reduce prototyping costs and lead time for product development.

 

eta/DYNAFORM’s analysis engine is LS-DYNA, which is developed and currently supported by the Livermore Software Technology Corporation (LSTC) of Livermore, California. It is a general purpose, non-linear, dynamic, finite element analysis code utilizing explicit and implicit capabilities for solving fluid and solid structural problems. The code has been developed for applications such as automobile crashworthiness, occupant safety, underwater explosion, and sheet metal forming.

 

The bottleneck of the metal forming development cycle is the hard tooling design lead-time. The eta/DYNAFORM CAE approach simulates this tooling process and thereby reduces the tooling tryout time and the associated cost for producing high quality stamped parts. eta/DYNAFORM effectively simulates the four major design concerns in the tooling process: Binder Wrap, Draw Die, Spring Back, and Multiple Stage Tooling. These simulations enable engineers to conduct feasibility studies of a product design early in the design cycle.

 

eta/DYNAFORM features well-defined tooling surface data to predict the performance of a stamping for areas such as tearing, wrinkling, and thinning, in addition to predicting skid mark and spring back effects.

 

Availability:

eta/DYNAFORM is available for all UNIX workstation platforms including DEC(Alpha), HP, IBM, SUN, and SGI.  It is available on PC for Windows and NT operating systems of 1998 and above. For LINUX, the Red Hat version 7.2 and above is supported.

 

Special features of eta/DYNAFORM Version 5.6 include:

 

A process oriented module- AUTOSETUP

This module has been greatly improved in the eta/DYNAFORM 5.6.  The multi stage simulation setup provides a complete scheme for solving stamping problems and allows the user to set up line die simulation. This module is process oriented and enables user to easily set up all types of simulation.

 

AUTOSETUP allows the user to define stamping direction, forming simulation of tailor welded blanks, hydroforming simulation, multi stage simulation and trimming operation. In addition, Superplastic forming simulation and thermal forming simulation are added to this module. The enhanced material library in Auto Setup module allows the user to add the standard material library for corporations to the program interface for easier selection of common used materials.

 

SCP module

Springback Compensation Process (SCP) is a new module in eta/DYNAFORM 5.6 for die compensation of sprung sheet metal parts. Springback is one of the crucial issues for sheet stamping industry. The springback compensation based on finite element technology is utilized to alleviate the severity of springback phenomena. SCP is used to modify the original die face with the springback quantity generated from springback simulation to make the part dimension to fall within the tolerance of intended part design after springback. The eta/DYNAFORM also provides some practical tools for the user to repair the compensated die face and improve the efficiency for die face design.

 

Update Drawbead function

The Drawbead function is updated in eta/DYNAFORM 5.6. The GUI of drawbead and operation style is overhauled to facilitate easy drawbead definition and modification. All operation in drawbead generation, including property definition, create, edit and restrain force definition, can be easily performed without advanced training.

 

More functional DFE module

Compared to previous version, many functions in the DFE module of eta/DYNAFORM 5.6 are improved and added to satisfy the needs of the friendly and functional operation. The user can quickly import the product and complete the entire process of die face design. The major improvement includes:

 

Ø   Added SIDE-STEP function. This function enables user to extend part boundary and provide side-step features for the subsequent addendum creation.

Ø   Added DOUBLE ATTACH function. The user can design double attached die face by two part geometry. This function can be used with SYMMETRY function.

Ø   Improved TIPPING function. The wall angle and wall angle contour can be displayed enabling the user to view the variation tendency of wall angle.

Ø   Binder module has been completely overhauled in eta/DYNAFORM 5.6. Many new functions are added to this module to satisfy the user’s design requirements for various binder shapes. The user can easily modify the desired binder shape by adding control lines. In addition, the user can also design the flange binder and butterfly shape on binder.

Ø   Improved addendum module. In this module, many functions are integrated to simplify the editing and modification process. The algorithm of addendum generation has also been improved and optimized for the user to design more reasonable addendum.

Ø   Improved RE-ENGINEERING module. The GUI of this module is enhanced. Some auxiliary functions are added for the user to convert the original addendum to the new addendum in eta/DYNAFORM. Additional functions are provided to modify the new addendum.

 

Enhanced BSE module

In eta/DYNAFORM 5.6, trimline module is a brand new module utilized to compute trimline using the modified one-step solver developed by ETA. In addition, the user can perform multiple localized unfold operation using the Multi Unfold module in BSE. The blank nesting capabilities have also been improved and optimized. For nesting of complicated parts, the nesting result yields higher material utilization rate and more practical nesting pattern.

 

Implement Rotary Draw Bending

Rotary Draw Bending is a newly developed Quick Setup module for tube bending analysis. The module is equipped with user-friendly and process oriented GUI. Furthermore, the module enables users to easily tube bending model.

 

 

 

Enhanced Pre-processor functions

Ø   Rearranged the functions for line/point, surface, element and node with the sequence of create, delete, modify/edit, transform and display.

Ø   Added Shortest Curve function, which allows the user to calculate the shortest curve between two points in element and the total curve length exceeding two points.

Ø   Improved Boundary Line function, which allows the user to create line along the boundary of finite element mesh or surface boundary.

Ø   Added S-Line function to Line/Point menu.

Ø   Improved Section Line function.

Ø   Improved Modify Line function, which allows the user to modify lines by adding, moving, deleting points on the line.

Ø   Added new transformation function. Integrated the Translate, Rotate, Mirror and Scale functions for line, surface, element and node. Added LCS2LCS function for the user to perform transformation operation on line, surface, element and node.

Ø   Improved line RE-SPACE function.

Ø   Added Mesh to Surface function, which allows the user to generate surface from mesh.

Ø   Improved Surface Split function.

Ø   Added Extend Surface function, which allows the user to extend the untrimmed surface of outer boundary.

Ø   Added Check Surface function, which allows the user to check tiny surface, surface boundary, control points distribution and surface intersection.

Ø   Improved Surface Mesh function.

Ø   Improved Drag Mesh function.

Ø   Added Trim Element function, which allows the user to trim elements with one or multiple closed or unclosed trim lines.

Ø   Added Lance Element function, which allows the user to lance the selected element along one or multiple specified paths.

Ø   Added Mesh Surface Deviation function in Model Check/Repair, which allows the user to measure the deviation between surface and element.

Ø   Improved index file for the user to transfer information such as FLC and drawbeads from Preprocessor to Post-processor.

Ø   Improved Animate function in Tool menu.

Ø   Improved Identify Node/Point function, which allows the user to select multiple nodes/points and auto display the numbers of the selected nodes/points on the screen.

Ø   Added LCSLCS ENT TRANSFORM function in Coordinate System, which allows the user to copy or move lines, surfaces, elements and nodes as well as their thickness, stress, strain information from one LCS to another.

Ø   Improved Light function View Options menu.

Ø   Added Background Color function in View Options menu, which allows the user to change the background color.

Ø   Added #25 and #26 shell element formula, Thick shell and Solid element formula.

Ø   Added Coarsening and Interface Force options in Forming Analysis.

 

Documentation

A Training Manual is available to assist first time users with the general operating procedures of the program. The manual includes a relatively simple demonstration of a draw die simulation of an S-channel. The step-by-step procedure guides users through the complete process and flow of tasks.  A new user can usually complete the training program and be ready to begin a production project in less than two hours.

The eta/DYNAFORM Applications Manual discusses the basics of the sheet metal forming process and transmits some fundamental knowledge of tooling design and related topics to the user.  The following are typical examples of simulations that are included to demonstrate eta/DYNAFORM’s capabilities, features, and functions:

Case 1.  NUMISHEET’2002 Fender Draw Simulation

Case 2.  Double Action of Hemisphere Draw Simulation

Case 3.  T-Shape Tubular Hydroforming Simulation

Case 4.  NUMISHEET’2002 Fender Gravity Simulation

Case 5.  Tailor welded blank and Multi-Stages Simulation

Case 6.  U-Channel Springback Simulation

Case 7.  Cup Sheet Hydroforming Simulation

These workshop examples enable users to fully understand general pre- and post-processing operations in addition to the applications of binder wrap simulation, draw bead force calculation, draw die simulation, Forming Limit Diagram (FLD), thickness, thinning, wrinkling, and springback simulation.

 

Support LS-DYNA 971 R3

The input file created by eta/DYNAFORM 5.6 supports LS-DYNA 971 (42681 version) format. The eta/DYNAFORM User’s Manual describes functions of the software interface. For further details about solver, please refer to the LS-DYNA User’s Manual published by the LSTC.