I found that starting with simple elements like beam elements helped understand the concept initially. I did a few calcs by hand (using stiffness matrices) and checked them against Nastran results for the same basic problem. Its fiddly but I learned a lot this way about the importance of a few...
Hi!
OK I worked it out. The modification to the force vector was tripping me up. Attached is my final spreadsheet. I was trying to basically represent the same problem two ways: applying a load to one end, or by enforcing a displacement that achives the same reactions.
The spreadsheet isnt...
Here attached is a spreadsheet I made to for this problem.
The first worksheet "Displacements" uses excel to invert the assembled stiffness matrix and solve for given load (-35000N).
I remove column and rows by replacing the stiffness terms (for zero displacement DOF) with zeros except for the...
Hello,
unfortutely my book doesnt have an enforced displacement example. I tried partitioning the matrix as you described, but I dont seem to get the right answer.
I am doing it wrong, I think, is it right to remove rows and columns associated with DOF that have no enforced displacement?
In...
Hello anyone Im new to FEA and I am trying to work a few things out.
I understand that when you know what your applied loads are, and F=KX, the displacement can be calculated using KinverseF=X applied to a reduced stiffness matrix (where zero displacements are 'eliminated' from the stiffness...