Non-Linear Finite Element Analysis (FEA)

Non-Linear FEA

The behavior of a structure under applied loads is of utmost importance to engineers. Most engineering problems are non-linear from the beginning or they become non-linear at higher load levels. The nonlinear response could be due to different reasons e.g. material behavior,  snap-through, buckling or contact with a neighboring body. The finite element analysis (FEA) is widely used for solving the engineering problems in solid and structural mechanics. Solving non-linear problems using FEA is a challenging task even for an experienced analyst.

Solving Non-Linear Problems

A structure could exhibit non-linear behavior in many different forms and there could be a number of different sources of non-linearity. Solving such problems could be baffling to a novice user. One of the most difficult decision facing an FEA analyst is to decide whether a non-linear analysis is really required for a given problem.

Course Overview

Many courses are available on the topic of advanced finite element analysis providing details of the techniques available to solve nonlinear problems. These courses give a good insight into the basic theory, however these are not sufficient for a CAE Engineer/Analyst to solve complex problems in a FEA software. This course aims to provide practical information to perform complex nonlinear analysis in Abaqus, which is one of the best software to perform such analyses. This course takes step-by-step approach and presents from introductory to advanced technique in a gradual way. It is fundamentally different from the conventional teaching in a way that it adopts Problem-Based Learning approach. It consists of tutorials providing intensive instructions to perform analysis of nonlinear problems. During such analysis it is very common to face convergence difficulties. Quite a few tutorials are devoted to diagnose such difficulties and take the corrective action.

Course Details

The objective of the course is to give an overview of the physics involved in nonlinear problems and show how to choose the best solution strategy. The course begins with an introduction with basic theory elaborated with graphs and pictures with minimal number of the mathematical equations. In this introduction, an overview of sources of nonlinearities in structures and solution algorithms available are described.

The exercises begin with simple problems having a single non-linearity and presents the appropriate techniques to solve it. Later in the course more complex problems are presented. Details of topics covered in exercises can be downloaded as PDF files in the download section. Following links show the details covered in some of the typical exercises.

Downhole Packer Seal

Bending of a Staple

O-ring Seal

X-ring Seal

U-cup Seal

Deep drawing of a cup

CAE models are accompanied for the user practice. Finished models are also available for download.

Who Should take this course?

The course is aimed at engineers/analyst who have basic knowledge of FEA and want to learn more about nonlinear analysis techniques in a practical way. It is expected that an attendee is familiar with the interface of  Abaqus. After taking this course, you will be able to solve complex FEA problems and take the appropriate diagnosis if convergence difficulties arise.