Finite Element Analysis of Engineering Components

School of Engineering and Computer Science

Page 1 of 6

COURSEWORK ASSIGNMENT

Module Title: FEA & Applications

Module Code: 7ENT1059

Assignment Title: Finite Element Analysis of Engineering Components

Group Assignment (3 students per group)

Tutor: Opus David-West

Internal Moderator: Mahmoud Chizari

Student ID Number ONLY:

Year Code:

Marks Awarded %:

Marks Awarded after Lateness Penalty applied %:

Penalties for Late Submissions

• Late submission of any item of coursework for each day or part thereof (or for hard copy submission only, working day or part thereof) for up to five days after the published deadline, coursework relating to modules at Levels 0, 4, 5, 6 submitted late (including deferred coursework, but with the exception of referred coursework), will have the numeric grade reduced by 10 grade points until or unless the numeric grade reaches or is 40. Where the numeric grade awarded for the assessment is less than 40, no lateness penalty will be applied.

• Late submission of referred coursework will automatically be awarded a grade of zero (0).

• Coursework (including deferred coursework) submitted later than five days (five working days in the case of hard copy submission) after the published deadline will be awarded a grade of zero (0).

• Where genuine serious adverse circumstances apply, you may apply for an extension to the hand-in date, provided the extension is requested a reasonable period in advance of the deadline.

Please refer to your student handbook for details about the grading schemes used by the School when assessing your work. Guidance on assessment will also be given in the Module Guide.

Guidance on avoiding academic assessment offences such as plagiarism and collusion is given at this URL: http://www.studynet.herts.ac.uk/ptl/common/LIS.nsf/lis/citing_menu

If the assignment is laboratory based (though not computer-based), or involves offsite activity, please attach the risk assessment form for the Internal Moderator to see.

UNIVERSITYOF HERTFORDSHIRE

School of Engineering and Computer Science

Page 2 of 6

ASSIGNMENT BRIEF

Students, you should delete this section before submitting your work.

This Assignment assesses the following module Learning Outcomes (Take these from the module DMD):

1. Explore the underlying physical principles and numerical methods of CAD and FEA Techniques

2. Use appropriate material properties, physical properties and boundary conditions for CAE models.

3. Critically evaluate simulation results from complex problems requiring advanced solution methods using industry standard post processors and analytical techniques

Assignment Brief:

• Complete all tasks in FEA Assignment 1 and FEA Assignment 2

• Write a report in which you should consider the aspects requested in the task sheets.

The page number of your report should not exceed 10 pages. Your report should be submitted as ONE document ONLY through the StudyNet/Canvas by ONE member.

No hard copy is needed.

Submission Requirements:

The page number of your report should not exceed 10 pages. Your group report (3 persons per group) should be submitted as ONE document ONLY through the StudyNet/Canvas by ONE member.

SRN numbers of the group members should be written on the front page.

No hard copy is needed.

This assignment is worth 25 % of the overall assessment for this module.

Marks awarded for:

See marking guide below.

A note to the Students:

1. For undergraduate modules, a score above 40% represent a pass performance at honours level.

2. For postgraduate modules, a score of 50% or above represents a pass mark.

3. Modules may have several components of assessment and may require a pass in all elements. For further details, please consult the relevant Module Guide or ask the Module Leader.

Typical (hours) required by the student(s) to complete the assignment: 20 hours

Date Work handed out:

6th March 2020

Date Work to be handed in:

3rd April 2020

Target Date for the return of the marked assignment:

Within 4 weeks

Type of Feedback to be given for this assignment:

Comments on marks document through StudyNet / Canvas.

UNIVERSITYOF HERTFORDSHIRE

School of Engineering and Computer Science

Page 3 of 6

Note: All sources used must be referenced using Vancouver or

Harvard referencing style.

FEA Assignment Task1: (65%)

LINEAR ANALYSIS and MODEL UPDATING

In present day structural dynamics, finite element tools are used to simulate the dynamic behaviour of

structures under several operating conditions and this usually includes some simplification /

assumptions in the development of the analysis; usually the initial numerical result does not match the

dynamic characteristics of the real structure, hence it must be updated to reduce the degree of mismatch.

In this task you are required to:

Create a finite element model of the box shown in Fig. 1 made of steel of which typical elastic properties

are presented in Table 1. The box is hollow at the bottom and in Fig. 2 is a schematic of the structure

with the dimensions shown.

TASK 1A: 45%

Conduct a vibration analysis and update the initial analysis result to predict the experimentally obtained

natural frequencies shown in Table 2 which were extracted from the experimental frequency response

plot. Also presented in Table 3 are the mode shapes from the experiment.

Fig. 1: Photograph of box

Fig. 2: Schematic of box

Table 1: Elastic properties of steel

Modulus 200 G Pa

Poisson’s ratio 0.3

Density 7830 kg/m3

UNIVERSITYOF HERTFORDSHIRE

School of Engineering and Computer Science

Page 4 of 6

Table 2: Experimental natural frequencies

Mode number

Natural frequency (Hz)

1

16.99

2

20.01

3

23.47

Table 3: Experimental mode shapes

Your report should be presented technically to include the following:

o Concept of the dynamic analysis implemented

o Geometric modelling strategy

o Choice of elements

o Discretisation and boundary conditions implementation strategies

o Three mode shapes

o Comparison the numerical and experimental results.

o Initial set of natural frequencies and the updated set of natural frequencies

o Explanation of the model updating strategies

TASK 1B 20%

It is required to change material used in the construction of the box in Fig. 1 to an advanced material with orthotropic properties; highlight the challenges of included the material model to run the finite element analysis?

UNIVERSITYOF HERTFORDSHIRE

School of Engineering and Computer Science

Page 5 of 6

FEA Assignment Task 2: (35%)

Consider a 0.3 m square aluminium plate of thickness 2.5 cm with a centrally located circular hole of 1.3 cm radius as shown in Fig. 3. It is subjected to a pressure on either side of 7 MPa on both ends.

The properties of aluminium are written in Table 4.

TASK:

o Create a nonlinear finite element model of the loaded aluminium plate and run the analysis.

o Obtain the change in length from the numerical model and compare with a simple analytical result.

o Present the discretization and possible stress result (eg stress intensity)

o Explain the result presented, stating possible suggestion for improvement to reduce tendency for early failure.

Fig. 3: Schematic of hollow plate

Table 4: Mechanical properties of aluminium

Modulus

76 GPa

Poisson’s ratio

0.33

Yield stress

275 MPa

Tangent modulus

1.33 GPa

UNIVERSITYOF HERTFORDSHIRE

School of Engineering and Computer Science

Page 6 of 6

Fig. 4 is a schematic illustration of bilinear material model.

Fig. 4: Bilinear material model

MARKS ASSESSMENT STRATEGY

REPORT STRUCTURE

(5 marks)

INTRODUCTION

✓ Technical explanation of the phenomena plus references and industrial application

✓ Select a citation style and keep consistency throughout your report.

(10 marks)

ANALYTICAL

✓ Understanding of the problem

✓ Justification and engineering understanding of approach used.

(10 marks)

SIMULATION

✓ Geometry and discretisation

✓ Judgement of discretisation.

✓ Interpretation and inclusion of parameters

✓ Loading and analyses

✓ Extraction of results and analysis

(30 marks)

DISCUSSION

✓ Explain the results obtained.

✓ Justification of methods used

✓ Interpret the significance, stating useful suggestions.

(25 marks)

CONCLUDING REMARKS

(15 marks)

REFERENCES

(5 marks)