Program Notes

[NNNOTNERD]

Dear Yeuyo

Thanks for you great work on nonlinear FEA. But I can understand it vary well. For example:
nDoF=nodes5;
neDoF=(95)^2;
What is the function of parameter neDoF？And many parameters，I can't understand it very well.
So,Could you please give a more detailed manual about Program?

Thanks a lot.

Best regards
yang

[Yeuyo]

Dear Yang,

Sorry for the late reply.

nDoF is the number of Degree of Freedom for each element.
In this case, we have 5 degrees of freedom at each node (displacement along x-axis, displacement along y-axis, displacement along z-axis, rotation about local x-axis and rotation about local y-axis [refer to page 90 of the Thesis for more details]).
This result in the nDoF = nodes * 5.

neDOF = (9 * 5) ^ 2 is the number of element's Degree of Freedom, in this case, we have 9 nodes per element, that's where the 9 comes from.
I wanted to make use of MATLAB's sparse matrix function, so I converted my Stiffness Matrix into a huge diagonal sparse matrix, this resulting in needing a Sparse matrix of n^2 of size (for example, if I want to store relationship values between 2 variables in a matrix that only store values along its diagonals, I would need a matrix of n ^ 2 rows and columns [to store values from a 2 * 2 matrix, which has 4 values, a 4 * 4 matrix is required]).

More information could be found in the my thesis I linked earlier.
Please do let me know if there are specific things you are unclear about.

Regards,
Yeuyo