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# Lab2draft(1)

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Abstract:(WRITE MORE, EXPLAIN EVERYTHING IN ABSTRACT) DO IT HALF PAGE. Discuss results This experiment was mainly aimed at determining the impacts of stress on photo elasticity The purpose of this experiment is to find introduce photo elasticity and its application to stress as well as to introduce finite element analysis and its application. Using 3 different methods and also to become familiar with FEA the value is found by using results from FEA through hand calculations and by using proper engineering decision making.Table of contents: Abstract…………………………………………………………………………………………………………………………1 Introduction…………………………………………………………………………………………………………………..3 Methods………………………………………………………………………….……………………………………………..4 Results…………………………………………………………………………………………………………………………..5 Discussion and Conclusion………………………………………………………..…………………………………..7 Appendix……………………………………………………………………………………………………………………….8 Introduction:
(need background information +write about the machine and what is the final analysis, write what we will in the experiment. Stress concentration within a given part can be observed by use of photoelasticity, whereby light is projected onto the given part and the emerging reflection is then viewed through a Polari scope to view the fringe count on the surface. Leven, M. M. (Ed.). (2013). We usually neglect stress concentrations that are at pinned ends under a constant tensile load but rather use plate of plastic that is sufficient in length to distribute the tensile load evenly before getting to the region of interest. That is where we want to find stress concentrations. By using the dimensions away from the supplied tensile force ensures accuracy of our measurements is of high percentage.Doing this experiment is to introduce photoelasticity and its application to stress as well as to introduce and find finite element analysis (FEA) and to find the Kt by Using 3 different methods. The value is found by using results from FEA through hand calculations and by using proper engineering decisions making.The governing equations were:F/A+…../Istress from axial and moment force….(F/A+…../I)maximum stress value at critical point. Figure 1: shows the model drawing and dimensions. Figure 2: Shows the Polariscope device. Methods:  (WRITE MORE AND CHECK MY FRIENDS REPORTS)+ write about the equations + and how did we used the machine) write that we are 5 members in a group and each of us did a reading and like this ) Our specimen was measured and the points of nominal stress marked.  The polascope was turned on after which the cell was loaded and adjusted to 30% and the load cell zeroed. We then attached the specimen to Polari scope of specimen in a manner parallel with plane and lens. This was particularly done with polariscope at “M” position, together with which a load was added to ensure it doesn’t break. We had to hold the fringe compensator’s longitudinal axis parallel to us. Figure 3:  Shows the 2-D dimensions for the prototype. The fringe was then zero ordered until around 240 and we did it 10 times. During which we recorded the dial and repeated the step 10 times on marked nominal stress point then we unloaded the specimen and consequently removed the polariscope.Figure 5: Shows the design in FEA with the applying loads.Figure 6: Shows the stress in the design in FEA.Results:  (CHECK MY Friend’s work, the last attachment as word file) – and then write here more in the results, write the calculation as words, – Table for the data collection Compensator Dial Reading Point 1 Point 2 Point 3 60 51 107 65 52 114 55 46 108 56 49 106 57 49 103 This table shows the 5 readings for each point that was done by the group members.-The average for the data collection:  1. Point 1:   2. Point 2:          3. Point 3:    Discussion and Conclusion: Write about the introduction + discuss the result + what we found + your opinion + write how you could improve the experiment in the future) Appendix:(References & original data)ReferencesLeven, M. M. (Ed.). (2013).Photoelasticity: The Selected Scientific Papers of MM Frocht. Elsevier.