Industrial Applications of The Finite Element Method

 55-702024 Industrial Applications of The Finite Element Method

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Submission Date: 3pm Thursday 14th August 2020

(50% of Module Mark)

Problem Outline

FEA tools can help predict the stresses and therefore, points of failure in many materials. Often physical testing (such as ASTM standards) uses a pre-notched sample in order to produce a reliable and consistent location of failure. In this exam, stresses will concentrate around a hole which has been punched through a solid, rectangular plate.

The main objective of this specific assignment is to predict the stress in the plate through the use of finite element analysis commercial software.

Geometry

 Please note that all measurements are in mm.

 The hole is located in the very centre of the plate and has a diameter of 0.25mm, passing completely through the plate's thickness.

 The plate has a total length of 4mm and a total width of 1mm.

 The plate has a depth of 0.135 mm.

55-702024 Industrial Applications of The Finite Element Method Coursework Assignment 2019-20

Referral Coursework Task 1

FEA Analysis of a Loaded, Symmetrical, Holed Plate

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You are expected to provide a suitable method of modelling this geometry in either 2D or 3D, and to:

 Estimate and adapt loading conditions

 Apply suitable boundary conditions that represent the use of the part

 Partition and mesh the models without guidance

 Adapt the geometrical features of the part to minimise stress

SOLVING THE PROBLEM - A BASIC GUIDE

This part may be modelled in 2D or 3D. You need to apply enough loading so that the yield stress of the material is exceeded.

Integrating the Model

Basic Material and Static Loading conditions are supplied below. Please note you will be expected to adapt these conditions to cause the maximum stress in the material to exceed the plastic limit.

 Load at Top Edge of Plate = +10kN

 Load at Bottom Edge of Plate = -10kN

 Material = Stainless Steel, AISI Type 304L Stainless Steel

 Material: Density = 8000 kg m-3, E = 196.5 GPa, Yield Stress = 210 MPa. You will need to find an appropriate value for Poisson's Ratio.

 Assume that plastic deformation occurs at point of the yield stress.

Sections, Symmetry and Meshing

A suggestion on how to implement the geometry is given below. Please note this is only a guide and is not an instruction. You will be expected to vary this suggestion in order to manage the stress and extension in the plate. You may use 2D, Axis-symmetric, or 3D modelling as you prefer.

Suggested Suitable Section setups are:

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 2D Axis-symmetrical (as illustrated above)

 2D (Apply a Homogenous Section, with more than one BC = Symmetrical)

 3D (Homogenous Solid Section, with several possible BC's)

You must complete a full report on your findings.

 For all parts, a full report that details the modelling and stress analysis is to be submitted (10 pages max) and the Abaqus files for your modelled part.

 Staff support in CAD Labs for 55-702024 for your coursework is limited. You may use the SHU facilities at any time, but do not expect to be allocated extra resources for this coursework.

 You will be expected to work fully independently. You should not submit any work that is the result of collaboration.

Goals

Goal 1: To produce an accurate geometrical model of the part in question, using appropriate materials and boundary conditions. This can be done with any software available. Reporting on meshing, seeding, element choice and any mesh refinements should be included. The following items should be delivered:

 2D or 3D Sketches

 Axis-symmetric or 3D Parts

 Material properties (Young's, Poisson's ratio, Yield Stress - appropriately referenced)

 Boundary Conditions (fixed points, symmetries, supports, etc.)

 Seeding & Meshing

 Element types and justifications

Goal 2: To predict the structural performance of the plate, and make recommendations for design improvements. You will be given basic loading conditions to start the model working, but will need to estimate more appropriate static loadings that reach the point of yield stress in the material. This section should include several appropriate recording of values concerning:

 Extension of the plate under loading (mm)

 Stress (Max. Principal, Von-Mises),

 Yield Stress of material(s) with reference to appropriate safety factors,

 A Convergence Study (i.e. Stress of one element vs. Number of elements, or Extension of plate vs. Number of Elements).

Goal 3: To improve the mesh such that the stress can be studied in more detail. This should involve reducing the seed and element sizes that are around the notch, and therefore of higher stress values. You may also change the minor features of the part (hole diameters, fillets, chamfering) in order to reduce stress concentrations. Different grades of material may be substituted to improve the load-bearing potential. This section should include findings on:

 Maximum Stresses at Notched Hole AND Extension of the Plate

 Partitions, Seed Bias, and other Meshing Tools

 Introduction of improved material choices (use a different steel or material) All changes and results should be reported in a concise, technical format.

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Deliverables

1. Individual: Abaqus files x2. Include .cae and .jnl files for marking.

2. Individual: Word-processed technical report, 2000 words (maximum recommendation), .pdf format, electronic submission. Max length - 10 pages.

Deadlines

1. Submission date 14th Aug 2020, 3pm. Report file and *.cae & *.jnl files to Blackboard.

2. If using the STUDENT VERSION of Abaqus, just a *.cae file and report are acceptable.

3. Returned: within 1 month of submission.

Notes

This assignment carries 50% of the overall module marks which are broken-down as follows:

 Task 1 - Report (individual work): 50%.

 Task 2 - ICTA: 50%.

 Materials Info on 304L Steel: http://www.matweb.com/search/datasheet.aspx?MatGUID=e2147b8f727343b0b0d51efe02 a6127e

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Assessment Criteria

Criterion:

Weighting:

Distinction (100 to 70%)

Merit (69 to 60%)

Pass (59 to 50%)

Fail (49 to 0%)

Mark:

Geometry, Representation, and Mesh Selection (20%)

20%

Deep understanding of many geometric/meshing concepts demonstrated and robust justification of selected mesh given.

Understanding of a few geometric/ meshing concepts demonstrated and robust justification of selected mesh given.

Robust and correct justification of selected geometric/mesh choice given.

Little or no discussion as to why the choice has been selected. Or justification given is largely incorrect or not relevant.

H

M

L

H

M

L

H

M

L

H

M

L

FEA Analysis (20%)

20%

Technical understanding of FE demonstrated with appropriate and fully justified selection of modelling strategy. Proficiency in operating the software and performing post processing shown. Understand of the numerical methods is demonstrated.

Understanding of FE demonstrated with appropriate and justified selection of modelling strategy. Proficiency in operating the software and performing post processing shown. Aspects of the numerical methods have been discussed.

Modelling strategy is appropriate for simulation and some aspects have been thoughtfully discussed.

Ability to operate software is illustrated in report. Post processing is performed, but may not be appropriate for results discussed. Numerical methods not addressed.

Modelling strategy is inappropriate for simulation and with little justification as to why is has been adopted. Discussion consists of a list of options selected in software with little illustration of understanding why options have been selected.

H

M

L

H

M

L

H

M

L

H

M

L

Structural & Physical Fidelity(20%)

20%

The successful use of the model is demonstrated, in terms of errors and increments to the solution for key parameters. Higher-order spatial discretisation and mesh adaption, and higher-order numerical discretisation and advanced physics are used to achieve high fidelity results.

The successful use of the model is demonstrated, in terms of errors and increments to the solution for key parameters. Higher higher-order spatial discretisation and higher-order numerical discretisation are used.

Use and mesh concepts are understood, and some attempt is made at achieving refinement of the mesh. A plan of action for further development is presented, and partially completed.

Little understanding about what accuracy or fidelity mean in FEA or why they are important. Little indication that they have been applied. Obviously unphysical results not addressed.

H

M

L

H

M

L

H

M

L

H

M

L

Performance Assessment & Redesign (20%)

20%

Both qualitative and quantitative results are presented for the primary and derived variables which directly relate to performance, and the connection between cause and effect on performance is explored and clearly communicated, using pictures, data tables and succinct discussion and conclusive statements.

Both qualitative and quantitative results are presented for the primary and derived variables, with some connection between cause and effect on performance being explored and communicated, using pictures, data tables and succinct and conclusive statements

Both qualitative and quantitative results are presented for the primary and derived variables are communicated, using pictures, data tables and succinct discussion and conclusive statements are made.

Qualitative results are presented for the primary variables are communicated in their basic form, with little discussion or statements made.

H

M

L

H

M

L

H

M

L

H

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L

Advanced Development & Analysis (10%)

10%

Discretionary marks for students making an exemplary effort to increase the performance of the part. Top marks will be awarded for a technically proficient use of engineering application to justify design changes that would increase safety. The work presented should use demonstrate an above and beyond average ability with either an analytical or computational methodology or, ideally, a cohesive combination of both, and could involve model coupling, advanced physics or enhancement to the scope of the model.

A good effort to increase the performance of the part. Top marks will be awarded for a technically proficient use of engineering application to justify design changes that would increase safety. The work presented should use demonstrate an above and beyond average ability with either an analytical or computational methodology or, ideally, a cohesive combination of both, and could involve model coupling, advanced physics or enhancement to the scope of the model.

Some intuitive uses of engineering applications to justify design changes that would increase safety. The work presented should use demonstrate an verage ability with either an analytical or computational methodology or, ideally, a cohesive combination of both, and could involve model coupling, advanced physics or enhancement to the scope of the model.

Few or negligible technical improvements to the modelling are demonstrated.

H

M

L

H

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H

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H

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Presentation (10%)

10%

Report is of publication standards, language is precise and concise and report contains all necessary sections and well written abstract. All standards in marking proforma (on BB site) are adhered to. Referencing uses recognised standard (such as Harvard or

Vancouver)

Report contains all necessary sections and an abstract. All standards in marking proforma (on BB site) are adhered to. Referencing uses recognised standard (such as Harvard or Vancouver)

Report contains most of the necessary sections and an abstract. Most of the important standards in marking proforma (on BB site) are adhered to. Referencing is clear and consistent.

Report is poorly presented and many of the standards in the marking proforma (on the BB site) not adhered to.

Referencing style is poor or not used.

H

M

L

H

M

L

H

M

L

H

M

L

FOR A HIGHER SIZE PRINT PLEASE SEE BB ("Assessment" Tab)

55-702024 Industrial Applications of The Finite Element Method

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Normal University regulations regarding cheating, plagiarism and collusion apply, any student(s)

deemed to be in breach of these regulations will be required to attend an Academic Conduct Panel and this may result in a failure of the module. Please refer to the University regulations regarding cheating, plagiarism and collusion.

ELECTRONIC SUBMMISSION ONLY

Submit your work in the form of an electronic report (.pdf format) via the Blackboard link. If the file is too large, and ONLY if the file is too large, alternatively you could submit on either a CD/DVD via the Sheaf reception along with a completed assignment cover sheet. If you submit using Sheaf reception, please ensure you submit your work on or before 4pm Friday prior to or on the submission date specified above. Finally, make sure all your drawings/images/plots are clear, readable and are accompanied by a written explanation.

Failure to submit your assignment by the hand-in date will result in a non-submission and a mark of zero will be recorded. Extensions to the assignment hand-in date can only be granted by your Student Support Manager.

If you do not make a “valid attempt” in any of the assessment tasks in the module you will fail that task. A valid attempt must demonstrate engagement with the subject matter of the assessment set; for example, that some or all of the assessment criteria and learning outcomes are partially or fully met; and it must be capable of carrying a mark.

The minimum pass criteria for this assignment is 50%, this may be achieved by completing all or some of the assessment tasks previously described.