Cylindrical Hertzian Contacts- FEA Project

In MCE 466 - An introduction to Finite Element Methods we needed to explore a topic using finite element analysis methods and the program Abaqus. I chose to investigate stresses in Hertzian Contacts using two cylinders (One cylinder was 4 inches and the other was 6 inches, both stainless steel) . Stresses in Hertzian contact occur when two curved surfaces are pressed together.

In Abaqus, this problem was modeled in 2-D and also took advantage of symmetry in the y-direction. These simplifications allowed less mesh to be used over the entire cylinder but a much finer mesh to be used at the contact points. It is important that two different parts are used so one part can be moved on top of the other. These two parts are allowed to interact with it each by setting the bottom surface as the master surface and the top surface as the slave surface.



The boundary conditions that were applied were that the bottom semi-circle has to be constrained in both the x and y directions and also have a symmetric boundary condition applied to it. The symmetric boundary condition also has to be taken into consideration when applying the load, and the load has to be cut in half.
The academic version of Abaqus limits the nodes that can be used to 20,000 nodes which is another reason why applying the 2-D and symmetric boundary conditions are so important. The mesh around the contact point was quad dominated and reduced integration is unchecked.



This simulation was run using plane stress and plane strain and by comparing the results, it was shown that the plane strain simulations produced a better analysis. The plane stress was not able to determine stresses in the S3,3 direction while the plane strain analysis was able to. Additionally, the plane strain analysis converges with the theoretical values faster and has a lower percent error with the theoretical values as compared to the plan stress analysis.



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