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STUDY BEHAVIOUR OF DIFFERENT ELEMENTS IN ANSYS FINITE ELEMENT
SOFTWARE
ZAIDI BIN ZOLKEFLE
UNIVERSITI TEKNIKAL MALAYSIA MELAKA
SUPERVISOR DECLARATION
“I hereby declare that I have read this thesis and in my opinion this thesis is
sufficient in terms of scope and quality for the award of the degree of Bachelor of
Mechanical Engineering (Structure and Materials)”
Signature : ………………………………………
Supervisor’s Name : PROF. MADYA AHMAD RIVAI
Date : ………………………………………
STUDY THE BEHAVIOUR OF DIFFERENT ELEMENTS IN ANSYS FINITE
ELEMENTS SOFTWARE
ZAIDI BIN ZOLKEFLE
This Thesis Is Submitted In Partial Fulfillment of Requirement for the Bachelor Degree
of Mechanical Engineering (Structure & Material)
\
Faculty of Mechanical Engineering
Universiti Teknikal Malaysia Melaka
JUNE 2015
ii
DECLARATION
“I hereby declare that the work in this thesis is my own except for summaries
and quotations which have been duly acknowledgement”
Signatures : ………………………………
Name of Authors : ZAIDI BIN ZOLKEFLE
Date : ………………………………
iv
ACKNOWLEDGEMENT
First of all, I would like to give my sincere thanks to my supervisor,
Professor Madya Ahmad Rivai, for his guidance, inspiring motivation and helps
during the supervision of this project. I have been very fortunate to be the
chosen student under his guidance. His constant voice of advices and
constructive criticism, especially in writing this thesis has been my source of
inspiration.
I would like to thanks my parents for give me a moral support and spirit
to complete my final year project report. I would also like to acknowledge with
much appreciation to staff of Mechanical Laboratory, who gave the permission
to conduct the experiment for this project. They have given so much
cooperation to me during three-point bending test.
Lastly, I would like to say thank you to all Mechanical Faculty’s staff
especially Jawatankuasa Projek Sarjana Muda (JKPSM) which have provided
useful guidance and lots of information in order to write a good final thesis and
some tips in preparation for seminar presentation.
v
ABSTRACT
Finite Element Analysis (FEA) is widely used in engineering field, especially
in aircraft and structure engineering. Generally, it is a numerical method for solving
engineering problems with complicated geometries, loadings and material properties.
There are software that could be used to model and analyse FEA problems, such as
Abaqus. ANSYS software is usually used to perform analysis on Computational
Fluid Dynamics (CFD. The objective of this project is to study and investigate the
capability of ANSYS in modelling and analysing structural problems by using
different elements which are one-dimensional (1D), two-dimensional (2D) and three-
dimensional (3D) elements. The validation and verification of the result will be done
by comparison of analysis from ANSYS with experimental data, theoretical
calculation and comparing the analysis result from other software. From the analysis,
the distinction of the result from ANSYS with analysis of other software, theoretical
calculation and experimental data was not too high with the percentage of error of 1
percent to 10 percent. So, ANSYS can be an effective platform to carry out structural
modelling and analysing in Finite Element Analysis.
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ABSTRAK
Analisis Unsur Terhingga (FEA) telah digunakan secara meluas dalam bidang
kejuruteraan, terutamanya dalam kejuruteraan pesawat dan kejuruteraan struktur.
Secara ammya, ia adalah satu kaedah berangka bagi menyelesaikan masalah
kejuruteraan dengan geometri yang rumit, bersama beban dan sifat bahan yang
tertentu. Terdapat beberapa perisisan komputer yang boleh digunakan untuk
memodel dan menganalisa masalah FEA, seperti ABAQUS. Perisian ANSYS
biasanya digunakan secara meluas untuk melakukan analisis berkenaan masalah
Pengkomputeran Dinamik Bendalir (CFD). Projek ini bertujuan untuk mengkaji dan
mempelajari keupayaan perisian ANSYS dalam permodelan dan menganalisis
masalah struktur dengan menggunakan elemen yang berbeza iaitu elemen satu
dimensi (1D), elemen dua dimensi (2D) dan elemen tiga dimensi (3D). Pengesahan
dan pengukuhan akan keputusan yang telah dianalisis menggunakan perisian ANSYS
akan dibandingkan dengan keputusan dariapada ujikaji, pengiraan teori dan
perbandingan bersama hasil analisis daripada perisisan yang lain. Merujuk kepada
hasil analisis, perbezaan keputusan perisian ANSYS dengan platfom yang berbeza
tidak terlalu tinggi dengan peratusan perbezaan hanya dalam 1 sehingga 10 peratus.
Jadi, ANSYS boleh menjadi platfom yang berkesan untuk menjalankan permodelan
dan analisis terutama sekali dalam Analisis Unsur Terhingga (FEA).
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CONTENT
CHAPTER TITLE PAGE
DECLARATION ii
DEDICATION iii
ACKNOWLEDGEMENT iv
ABSTRACT v
ABSTRAK vi
TABLE OF CONTENT vii
LIST OF TABLES x
LIST OF FIGURES xii
LIST OF GRAPHS xv
NOMENCLATURE xvi
APPENDIX xviii
CHAPTER 1 INTRODUCTION
1.1 Background of Project 1
1.2 Problem Statement 3
1.3 Objective 3
viii
1.4 Scope of Projects 4
CHAPTER 2 LITERATURE REVIEW
2.1 Project Review 5
2.2 Structural Analysis 6
2.2.1 Safety Assessment in Structural
Analysis 7
2.2.2 Phase In Structural Engineering 7
2.2.2.1 Planning Phase 8
2.2.2.2 Preliminary Structural Design 8
2.2.2.3 Estimation of Load 9
2.2.2.4 Structural Analysis 9
2.2.2.5 Revised Structural Design 9
2.2.3 Classification ofStructural Analysis 9
2.2.3.1 Tension Structure 10
2.2.3.2 Compression Structure 10
2.2.3.3 Shear Structure 11
2.2.3.4 Bending Structure 12
2.3 Method of Analysis 13
2.4 Bending Test 13
2.5 Finite Element 15
2.5.1 Finite Element Analysis (FEA) 15
2.6 ANSYS Finite Element Software 16
2.6.1 ANSYS Mechanical APDL 17
ix
2.6.2 ANSYS Workbench 18
2.6.3 Solid-Work 18
2.7 Modelling 19
2.7.1 1D Structural Modelling 19
2.7.2 2D Structural Modelling 20
2.7.3 3D Structural Modelling 20
2.7 Analysis 21
CHAPTER 3 METHODOLOGY
3.1 Introduction 22
3.2 Project Flow Chart 23
3.3 One-Dimensional Analysis 24
3.4 Two-Dimensional Analysis 27
3.5 Three-Dimensional Analysis 31
CHAPTER 4 RESULTS
4.1 Validation of One-Dimensional Element 36
4.2 Validation of Two-Dimensional Elements 38
4.3 Validation of Three-Dimensional Elements 39
CHAPTER 5 ANALYSIS AND DISCUSSION
5.1 Introduction 42
5.2 One-Dimensional Analysis 43
5.3 Two-Dimensional Analysis 45
x
5.4 Three-Dimensional Analysis 48
5.5 Discussion
5.5.1 One-Dimensional Element 52
5.5.2 Two-Dimensional Elements 53
5.5.3 Three-Dimensional Elements 53
CHAPTER 6 CONCLUSION AND RECOMMENDATION
6.1 Conclusion 55
6.2 Recommendation 56
REFERENCES 57
APPENDIX 60
xi
LIST OF TABLES
TABLE TITLE PAGE
3.1 Record of equipment for 3-point bend testing 26
3.2 Material properties of test specimen 27
3.3 Mechanical properties of cantilever beam 28
3.4 Material properties of I-Beam structure 32
4.1 Results of strain distribution for 3kN load from
Experiment 36
4.2 Results of stress distribution on nodes from
Equation 3.1 37
4.3 Result of stress distribution analysis between nodes in
ANSYS software analysis 38
4.4 Comparison of results between 5m and 10m element size 39
4.5 Comparison of stress and deformation of beam on
Solid-Work analysis 41
4.6 Comparison stress distribution results between
experiment data and ANSYS analysis 41
xii
5.1 Comparison stress results between experiment and
ANSYS analysis 44
5.2 Relation of error between results of ANSYS software
And 3-point bending test 46
5.3 Comparison of result between theoretical calculations
and ANSYS analysis with 5 meter element size 47
5.4 Comparison of result between theoretical calculations
and ANSYS analysis with 5 meter element size 47
5.5 Comparison of results between Solid-work analysis
and ANSYS analysis with tetrahedrons element method 49
5.6 Comparison of results between Solid-work analysis
and ANSYS analysis with Hex-Dominant element method 49
5.7 Percentage difference of results comparison between
Solid-Work and ANSYS with different element methods
for stress and deformation results 52
xiii
LIST OF FIGURES
FIGURES TITLE PAGE
1.1 3 Point Bend Analysis 2
2.1 Phase of a Typical Structural Engineering 8
2.2 Tension Structures 10
2.3 Column structure 11
2.4 Shear Wall Structural Analysis 12
2.5 Bending Structures 12
2.6 Bend testing of a rectangular bar under a) three-point
bend and b) four-point bend 16
2.7 Example of bend testing under 3 point bend experiment 17
2.8 1D (line), 2D (plane), and 3D (solid) elements 16
2.9 ANSYS Workbench interface for static structural 18
2.10 1D Beam Element 19
2.11 2D (plate) structural element 20
2.12 3D element structure 21
3.1 Project flow chart for PSM 23
3.2 Modelling 1-D structural beam on ANSYS 24
xiv
3.3 Aluminium beam with nodal points 25
3.4 Experiment setup for 3-point bending 23
3.5 Schematic diagram of experiment setup 26
3.6 Schematic diagram of cantilever beam 28
3.7 Applying the same element method
(quadrilateral dominant) different element size of
structural beam. 29
3.8 Modelling of structural beam and moment force
applied to beam 29
3.9 Schematic diagram of I-Beam structure with specific
Dimension 32
3.10 The I-Beam modelling method by using A) Solid-Work
and B) ANSYS software 32
3.11 Different method of elements was applied to
I-Beam structure A) Tetrahedron, B) Hex-dominant
elements 32
3.12 Stress application on the structure on A) Solid-Work,
and B) ANSYS 34
4.1 Point of reference point on 3-D structural analysis 40
5.1 Beam deflection analysis on ANSYS APDL 43
5.2 Analysis results on ANSYS software of two-dimensional
cantilever beam 46
xv
5.3 Structural Analysis results in ANSYS software on
I-Beam structure 48
5.4 Structural Analysis results in Solid-Work software
on I-Beam structure 49
xvi
LIST OF GRAPHS
GRAPH TITLE PAGE
5.1 Comparison between stress distribution result from
experiment data and ANSYS analysis on each nodes 44
5.2 Stress distribution results comparison of Solid-Work
analysis results with ANSYS analysis result on
different type of elements, Tetrahedron and
Hex-Dominant methods 50
5.3 Deformation of beam results comparison of Solid-Work
analysis results with ANSYS analysis result on
different type of elements, Tetrahedron and
Hex-Dominant methods 51
xvii
NOMENCLATURE
FE Finite Element
FEA Finite Element Analysis
FEM Finite Element Method
DSA Direct Stiffness Method
MSA Matrix Stiffness Method
CAD Computational Aid Diagram
CFD Computational Fluid Dynamics
GUI Graphics User Interface
APDL ANSYS Parametric Design Language
Emag Electromagnetic
Props Properties
Prosproc Proprocessor
1D One-Dimensional
2D Two-Dimensional
3D Three-Dimensional
3PB Three Point Bend
m Meter
N Newton
k Kilo ( X 103)
xviii
Pa Pascal
G Giga (X 109)
M Mega (X 106)
σ Stress
σx Normal Stress
E Modulus of Elasticity
σm Moment of Stress
I Moment of Inertia
ε Strain
εx Normal Strain
CHAPTER 1
INTRODUCTION
1.1 Background of Project
Finite Element Analysis (FEA) initially developed in 1943 by R. Courant, whom
responsible on THE RITZ method by relation of numerical analysis and minimization
variation calculus to obtain approximate solutions to vibration systems (Khairul S. &
Mariani Idroas, 2006). Chandrupatla & Belegundu (2012) state that for expositions
convenience, structural “Finite Element” may be divided into four generations that last
from 10 to 15 years. There are some evolutions of FEA of Matrix Structural Analysis
(MSA) into Direct Stiffness Method (DSM) from 1934 to 1970.
Started from the writer, M. J. (Jon) Turner at Boeing over 1950 to 1962, he
generalized and perfected the DSM and forcefully got Boeing to commit resources to it
while other companies were mired into the Force Method. Then, in addition to Turner,
major contribution to current practice include, B. M. Irons, inventors of ISO-parametric
models, shape functions, and frontal servers, R. J. Melosh, who recognize the Rayleigh-
Ritz link and synchronized the variation deviation of stiffness elements, and E. L.
Wilson, who developed the first open source FEM software (Boeraeve P., 2010).
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Then, M. J. Turner, R. W. Clough,, H. C. Martin, and L. J. Topp established a
broader of numerical analysis papers in “STIFFNESS AND DEFLECTION OF
COMPLEX SRTUCTURES”. Early 70’s, FEA was generally used in automotive,
defense, aeronautics and nuclear industries. With the increasing of technologies level,
FEA has been developed to an incredible precision for all kinds of parameters. FEM has
become the most powerful tool for the numerical solution of a wide range of engineering
problems. It can analysis in structures of heat flux, fluid flow, magnetic flux and
complex problems (Chandrupatla and Blegundu, 2012).
Figure 1.1 shows the example of analysis by using Finite Element Analysis
(FEA) on three-point bending test. It indicate the stress distribution towards the whole
beam.
Figure 1.1: 3 Point Bend Analysis
(Source: Erickson, et. Al (2010))
Nowadays, Finite Elements Analysis is used to express the mechanical behaviour
of a structure in engineering problems. There are three types of elements in finite
element that are 1D (one-dimensional), 2D (two-dimensional) and 3D (three-
dimensional) elements. For 1D, it is the simplest element, although lacking in their
ability to make modelling on complex structure. 1D commonly uses as a line modelling
to analyse any engineering problems with simple boundary condition and material
properties. 2D elements and 3D elements provide more details and even more
sophisticated results which require more complexity modelling on the structures. But,
3
the ability to gain the results on the Finite Elements also depends on the structures of the
elements and the capability of the computer itself to read the element structures.
1.2 Problem Statement
There are many engineering software that has the ability to model or analyze any
engineering problems. In performing structural analysis, especially for Finite Element
Analysis, there are software that capable to conduct modelling and analyzing such as
MSC Patran Nastran, ABAQUS, and ANSYS. But, in the industries, most of them adopt
MSC Patran-Nastran as the platform to solve structural problems. The application of
ANSYS software mostly covers on the Computational Fluid Dynamic (CFD) analysis.
For the exertion of ANSYS in finite element analysis only establish in late
1970’s where the initial product was to analyze the simulation of fluid flow in
engineering. There have been a deficiency of validation and verification of ANSYS
especially in finite element. This project therefore will review the capability of ANSYS
software to perform the modelling and analyzing of finite element structures.
1.3 Objective
To model appropriately the structural analysis problem in Finite Element Analysis
(FEA) by using ANSYS Software.