For this product I was the team leader of a 14-person team asked to investigate the catastrophic failure of a 737 fuselage. More specifically my team was asked to use various methods to prove that the failure could not have occurred suddenly without warning but slowly with clear signs of fatigue failure. To achieve this we used a number of solid mechanics techniques including mathematical formula and experimental procedures.
The above photo is a photoelastic material which changes color as stress is applied to it. The darker regions are those with higher stress values. This experiment provides us with value information about how material of a particular shape reacts to an applied load. More specifically it allows us to determine points of high stress concentration where failure is likely to occur.
The above image is a von Mises stress contour plot showing the results of finite element analysis on a steel member using ANSYS 12. The area in red is experiencing the highest compressive stresses and the area in dark blue the highest tensile stresses. This test is important as it shows a correlation between the physical test conducted using the photoelastic material and tests conducted using software.
It is unreasonable to insist on preforming physical tests because it is both expensive and time consuming. In many cases the part being tested only exists as a software model and it cost far too much to produce pieces only to destroy them searching for the ideal design.
The use of software packages has become the norm in industry and it is expected that new engineers are well versed in their function and operation.
The above image is a technical drawing of an interior fillet for a 737 fuselage produced using SolidWorks 2008. Below is the same fillet with operational stress loads applied to it. As can be seen in the image, the rivet holes produce the largest stress concentrations but even these are not so great as to cause sudden failure which red areas would indicate.
Like the finite element analysis conducted using ANSYS, SolidWorks represents a powerful software tool for producing and testing various designs. Both programs will prove beneficial during fourth year and as I enter the work force. Many companies in the manufacturing sector such as those in the automobile industry and mold making industry rely heavily on is form of technology and it would greatly reduce my employment options if I was not sufficiently versed in their use.