Assignment
The rational and optimal selection of materials underpins all engineering endeavours. In individual tutorials and class exams, you will practice various aspects of the materials selection process as follows:
i) defining a component function statement;
ii) identification of constraints;
iii) analysis of the relative importance of functions and constraints; iv) translating these to material properties;
v) conducting coarse screening using constraints (or limits); vi) derivation of one or more materials indices;
vii) short-listing materials using 2-d charts and selection lines etc;
viii) ranking short-listed materials using other methods including multi-objective analysis; ix) consideration of the influence of shape and
x) more detailed investigation of individual materials and their properties.
In this assignment, you will integrate all of these steps to conduct a complete and thorough selection of a material for an application. Some of the tutorial exercises will be directly relevant to your assignment (so you should save them) and others indirectly (i.e. the method will be valuable but the specific example will be different). The assignment (hard copy and electronic copy through Turnitin) is due by 5pm on Friday 11nd November 2013. The assignment is worth 15% of your overall mark for the Course. You are strongly advised to work steadily on the assignment each week as each topic is covered in the lectures and tutorials. You will not be able to complete it satisfactorily in the last week.
This is an individual assignment i.e. the submitted work is to be the work of an individual student. However, as the components you will be allocated are part of a larger system assigned to your laboratory group, a top-notch solution will be expected to include a small section at the end of the assignment addressing how your component integrates with the rest of the system and summarizing its overall attributes (primarily cost and mass) which will require you to share some information with other group members. If you wish, you can work on your assignment at the same time as other members of your group, recalling that the submitted work needs to be your own.
You will be required to submit a Turnitin similarity report with the hard copy of the assignment.
The systems under study will be internal combustion engines of 6 different types. For convenience one will be assigned to each laboratory group. Each student in each laboratory group will have a different component(s) to analyze and select materials for. As such, no two students will have exactly the same task to complete.
The 6 different engines and group allocations are:
i) A diesel engine for a family or touring car Group 3 Some components you could consider for analysis are: i) Pistons ii) Connecting rods iii) Crankshaft iv) Engine block v) Engine head vi) Valves vii) Camshaft(s) viii) Inlet manifold ix) Outlet manifold x) Fan or pulleys
xi) Big-end and small end bearings
Each group will need to meet and decide which component each member will work on. I suggest a random ballot if there is disagreement. You will need to indicate to your lecturer the component you have taken.
In order to complete the assignment you are urged to search out references concerning the design of engines as well as the general requirements for the type of engine you have been given. You can use our library holdings, the interlibrary loan service or try internet book sellers for a second hand copy (Amazon or Abe books are two well known ones). Reference books on machine design will help you identify the load case(s) for your component(s) on your kind of engine and the most important function (hence properties) although later we will study multi-objective analysis and I will expect a good assignment to use those methods so keep that in mind. A search on ENGINE DESIGN using Google gives a plethora of web-sites on the subject: many interesting (some not so useful).
Are you thinking "so what do I do now"?
My suggestion is: START NOW!
i) Decide quickly which component is yours
ii) Get hold of some reading and analyse the load situations (you don't need exact forces here!)
iii) Note any assumptions at the beginning
iv) Using the list in italics in the first paragraph on p1 as a guide, start working.
v) Don't be overly influenced by engines you have owned or seen and the materials they are made from. Be objective and wait until you have finished your own analysis. Then compare with materials currently used.
Assessment
Document each stage of your selection process in a word-processed report using 12 point TimesRoman or similar font with margins less than 2.5cm, hopefully not exceeding 15 pages in length.
You must address the following:
(i) Introduction and Assumptions
(ii) Translation (F, O, C, FV)
(iii) Screening
(iv) Ranking (MI, graphs, etc.)
(v) Competing Constraints / Multi-parameter Optimization
(vi) Shape, Manufacture
(vii) Conclusions