Wednesday, May 8, 2019

Solid Mechanics Assignment Lab Report Example | Topics and Well Written Essays - 2000 words

Solid Mechanics Assignment - Lab Report specimenAfter the regulate was imported to ALGOR FEA the log was checked to ensure that there were no import errors or missing geometry. Then a fixed boundary condition was utilise to the internal progress of the large cylinder after which a normal soak up of 500 N was apply to the internal egress of the smaller cylinder. The application of a fixed boundary condition to one area of the bewilder meant that the theoretical account was constrained from moving within that axis of rotation or translation. The model could either rotate on the longitudinal axis of the constrained cylinder or it could translate in either three distorts (x, y and z). Implementing a fixed boundary condition indicates that the model is unable to move in any direction at all. Generally a fixed boundary condition can be considered analogous to a welded piece that is unable to move but can bend or flex under applied tweet. Though this may not simulate the actual conditions one on one (where the crank truly rotates though it does not translate at all), but it does provide a satisfactory numerical probe model. Furthermore the application of a normal force to the other cylinders internal surface indicates the application of normal average force when the crank will be in use. This application of force assumes that the signal flag attached to the smaller cylinder of the crank will be able to transmit the applied force at the pedal completely and uniformly all across the surface of the cylinder and that this force will be normal to the provided surface. However practically this is not going to be possible as the pin will bear some kind of headroom to ensure free rotation and the clearance in turn will mean that the pin will tinge the cylinder non-uniformly. Moreover the pins contact will produce a normal force at areas with complete contact while they will produce slightly skewed forces where the cylinder only partially contacts the subject surface. This rule of applying a force to the model is non ideal yet the approximation is tolerable enough because what will say place inside the cylinder is similar. Any differences in force will not be precise significant so using normal forces application is a viable technique. The model was given a material of Steel 4130 which was present in the softwares library. After this the model was meshed using default settings. After meshing the model was simulated for calculating the developed stress and for the FOS (factor of safety) calculations. The results for the first run are shown below. The mesh was redefined for element size (which was lowered) although the mesh was still based on a 4 point Jacobian approach. The newly meshed model was then simulated in rate to see the effects of a changed mesh size on the numerical investigation. The results from the re-meshed run are shown below. The results higher up clearly indicate that the stress distribution levels and the FOS dist ribution did not change at all indicating that the foregoing mesh control was providing a mesh independent solution. Therefore for the purpose of this analysis and optimisation the forward mesh controls were re-implemented as a mesh independent solution had been achieved. The results above clearly show that the net FOS is very high which indicates a rather overdesigned scenario. The current situation dictates that the FOS ought to be around 31 for a viable design. In order to achieve a more suitable FOS the design was optimised for a

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