CAE - MECH 227 - Non Symmetrical Loading of a 90 Degree Angle - FEA Cosmos - Notes

1. Introduction
This provides an introduction to using Solid works Cosmos FEA to analysis the deflection and stresses in a 90 degree angle that is not loaded symmetrically.
The angle is assumed to be 50mm x 50mm x 5mm x 500mm length with a 5mm radius internal fillet made from aluminium.
The approach will be to start in Solid Works (Cosmos can only be started once a model is created or opened in Solid Works). Sketch the section, extrude it, specify the material, then start COSMOS. The load is applied to one end, the other restrained, the model meshed and the analysis run. The results are then assessed.

2. Method
i) When Solid Works has started, click on 'New' and select the 'Part' option and click 'OK'.
ii) Start 'Sketch', click on the 'Front' plane to sketch on, the plane then rotates to coincide with the screen.
iii) Select 'Line' and sketch the outline as shown below:

iv) Find the dimensions of the section as sketched and modify them to those required (above) by double clicking on them and entering the required values.
v) From the additional sketch commands select 'Fillet', click on the internal edges and enter the required radius of 5mm.
vi) Exit from the 'Sketch'.
vii) Using the 'Extruded Boss/Base', extrude the component 500mm.
viii) from the model tree in the lower left hand window, click on 'Material' and assign an appropriate material - eg aluminium 3003.
ix) Click on the 'COSMOSWorks' item from the top line menu.
x) Select 'Static' study and click 'OK'.
xi) Window in on one end and from the COSMOSWorks menu select 'Load/Restraint' then 'Force'. Apply 1000N acting in - Y direction on the end surface.
xii) Window in on the other end and apply fixed restraints to the other end surface.
xiii) Mesh the model, leave the controls as default.
xiv) Run the model.
xv) Review the results, expand the entries in the lower left hand model tree window and display the appropriate pictures. Looking at the 'front' of the beam (end on) it can be seen that the loaded end had moved down, sideways and the beam has twisted, which is how the demonstrated beam behaved.

David J Grieve, 3rd January 2006.