MEG 795 Special Topics: Energy Methods II

More Appropriate Title: Applied Dynamic Finite Element Analysis

Fall 2003 Syllabus Version 12.0 (Updated on 1/5/2004)

 

                                             Instructor:      Brendan J. O'Toole, Ph.D.

                             Contact Information:      Office: TBE B-122, Phone: 895-3885, e-mail: bj@me.unlv.edu

                                      Required Text:      Notes from O’Toole and Electronic Files Listed Below

                                    Reference Text:      Pilkey & Wunderlich, Energy and Variational Methods

                                                                  Belytschko, Liu, & Moran, Nonlinear Finite Elements for Continua and Structures

                                        Prerequisites:      MEG 741 or equivalent

 

Course Objectives     Course Outline     Grading     Homework     Projects     Final Exam     References/Acknowledgements     First Day Outline

 

Final Project Presentations

 
Course Outline

Week

Dates

Topics

1

W 8/27

Overview of Class

Overview of Available Software Tools: Hypermesh, LS-DYNA, LS-POST

2

W 9/3

Background and History of Dynamic FEA

General Capabilities, Analysis Process, and Detailed Capabilities

Submitting an LS-Dyna job, Post Processing and exercises

3

W 9/10

Time Step Control, Wave Propagation

FEA Modeling Techniques:

Initial Conditions, Boundary Conditions, Loads, Rigid Walls

4

W 9/17

FEA Modeling Techniques:

Constraints, Symmetry, Axisymmetry

5

W 9/24

FEA Modeling Techniques:

Preprocessing with Hypermesh for LS-DYNA

6

W 10/1

FEA Modeling Techniques

7

W 10/8

FEA Modeling Techniques Continued

 

W 10/15

Prof. O’Toole will be out of town.

8

W 10/22

Contact and Friction

9

W 10/29

Project 1 Due

Quasi-Static Initialization, Dynamic Relaxation

Damping, Mass Scaling

10

W 11/5

Contact/Impact Topics

11

W 11/12

Contact: Hourglassing

12

W 11/19

Boundary Conditions, Welding

13

W 11/26

Adaptive Meshing, Restarts, End of Semester Deadlines

14

W 12/3

Material Behavior II: Explosives, composites

 

W 12/10
Final Exam  6:00 – 8:00 PM

 

Final Project Presentations Fall 2003

Last Name

First Name

 Short Project Title

Doppala

Karthik

Blast on Cylinder 3

Dronavalli

Satish Babu

Flex test, Tube Crush

Feghhi

Masoud

Bolted Joint connections

Govindaraj

Elumalai

Notched tensile test 3

Hossain

Mohammad

Split Hopkinson Bar

Karpanan Nakalswamy

Kumarswami

Cylindrical impact

Lee

David

honeycomb core

Marthandam

Vikram

Notched tensile test 1

Matta

Kiran

AT595 blast container

Mullin

Michael

foam core

Nallani

Gopi

cylindrical Pressure loading

Naraparaju

Jagannadha

Impact hammer 3-pt impact test

Prabhakaran

Ramprashad

Blast on cylinder 1

Pusthay

Kiran Kumar

Blast on cylinder 2

Ransel

Christopher

Air gun pendulum

Sama

Sudheer

Dynamic crush of a can

Sridharala

Srujanbabu

G2a circuit board

Venkatesh

Anand

Notched tensile test 2

Wang

Hui

Tensile impact

Wilcox

Trevor

internal blast ALE

 

 

 

 Course Objectives

All students enrolled in this class should be familiar with energy methods in solid mechanics and the finite element analysis theory. This course will build on this background by providing an overview of computational analysis for dynamic systems. The overall objective is to become confident in using dynamic nonlinear finite element analysis programs for simulating applied problems. Specific objectives include:

 

 

GRADING:   

               Homework Assignments     20 %                                         Project 2     30 %          

                                      Project 1     30 %                                      Final Exam     20 %

 

Homework:

      There will usually be a computer simulation exercise assigned each week. This will be an exercise chosen to emphasize the class discussion for the week. They will not be graded unless specifically notified at the end of class.

      A few homework assignments will be assigned throughout the semester that will be turned in for a grade.

 

Projects:

      The bulk of the grade will be based on two applied projects. The projects can be done in groups of 1-3 people. Project topics must be approved by the instructor. These projects can be on any topic but they cannot be the same as example problems found in class or in the software manuals. Each project will have a written report (50 % of grade) and an oral presentation (50% of grade). Reports should be typed in a formal report format with table of contents, references, figures, etc. All figures, tables, and equations should be numbered and referenced in the body of the report. The written report will be graded based on technical content, writing quality, brevity, and completeness. The project report should include a:

·        Description of the problem

·        Detailed description of the FEA model used to simulate the problem describing:

o       Geometry

o       Boundary Conditions

o       Simplifying Assumptions

o       Material Models

o       Elements Used

o       Contact Algorithms

o       Control Cards

o       Etc.

·        Detailed description of your results including

o       Deformations

o       Stresses

o       Forces

o       or anything else that might be appropriate

·        Discussion of your results discussing the accuracy

o       Explain why it is accurate or why it is not accurate

o       How have you determined the accuracy?

·        Suggestions for improving the simulation and conclusions

 

You must also prepare a computer presentation of your project that should be approximately 15-30 minutes long. You must schedule a presentation date with the instructor before the written report deadline. Examples of reports and presentations will be presented during the first class.

 

Final Exam:

      There will be a final exam scheduled during Finals Week. It may include a closed book written test with general questions about topics covered throughout the semester and/or an assigned computer exercise.

 
References and Acknowledgements:

This course is based on several LS-DYNA and Nonlinear FEA short courses attended by Dr. O’Toole over the past 3-4 years. I would like to acknowledge the instructors of those courses:

 

John D. Reid, Ph.D., Mechanical Engineering Department, University of Nebraska-Lincoln, “LS-DYNA Introductory Training Class”, 4-day course at LSTC in Livermore CA, June 2000.

 

Paul A. Du Bois, H.E.N.V., “Crashworthiness Engineering with LS-DYNA”, 4-day course at LSTC in Livermore CA, July 2001.

 

M’hamed Souli, Ph.D., “Advanced Course in ALE and Fluid/Structure Coupling”, 4-day course at LSTC in Livermore CA, July 2002.

 

Ala Tabiei, Ph.D., Consultant, Associate Professor, Aerospace Engineering Department, University of Cincinatti, “Introduction to LS-DYNA”, 3-day course at Army Research Laboratory in Aberdeen MD, September, 2002.

 

Ala Tabiei, Ph.D., Consultant, Associate Professor, Aerospace Engineering Department, University of Cincinatti, “Multi-Physics Simulation Engineering”, 2-day course at Army Research Laboratory in Aberdeen MD, September, 2002.

 

T. J. R. Hughes and T. Belytschko, “Nonlinear Finite Element Analysis”, December 9-13, 2002.

 

 

First Day Outline:

·        Syllabus

·        Example of a project report

·        Example of a minimum presentation

·        Example of a good presentation

·        LS-DYNA Manager Window (Available Help Files)

·        Example Input Deck

·        Example Output Files

·        LS-POST Overview