Recent content by Ronankeating

Thanks for commenting, as you expressed node numbering schemes can affect only the optimization of global matrices but actually it shouldn't affect the result, right? Probably my issue is not completely related with node numbering scheme but instead with connectivity of elements. To be more...

Dear All, How important is the node numbering scheme for simple fem problems or is it important at all? It will be much easier to explain that by example, if I have following linear algebraic equations to solve with direct stiffness method \ K*\left\{X\right\}=F where K global stiffness...

Dear All, Thank you in advance does anybody can shed more detailed light on that one. Regards,

Can you elaborate that a bit more? How the K will be adjusted? That K is global stiffness matrix which depends on element cross sectional mechanical properties and X is global displacement/rotations matrix. After matrix multiplication two of them the result is F global load vector. The...

No doubt about that, But as I show in my previous post, sometimes we go directly for the solution originating from eigenvectors e.g. linear elasticity problems. Suppose that you solve an engineering problem K*x = F can you say that K*10*x = F is also solution, it really doesn't look very...

Dear All, In general eigenvalue problem solutions we obtain the eigenvalues along with eigenvectors. Eigenvalues are unique for each individual problem but eigenvectors are not, since the case is like that how we can rely that solution based on the eigenvector is correct. Because if solution is...

Yes SteamKing you've answered this question in the shown thread and thank you for your help, but if you remember I was looking additionally for the constrained type solution also where I couldn't find entry point. What inspires me actually to ask those question again, I still do have belief...

Dear All, If I have the linear algebraic system where its composed as of matrices in that form K*X=F, what column/row operations should I perform if I want to solve it where some of the X variables are known (targeted values) or if I want to solve when variables are constrained relative to...

Thank you in advance,

Thank you in advance SteamKing, That's another book worth reading which was not in my FEM library. After reading the suggested Appendix couple of questions comes in mind. The example given is fairly straightforward and easy to understand for the targeted displacements, it gives clear solution...

Dear All, I'm very familiar with the composition of finite element local stiffness, mass matrices as per any arbitrary element rod, beam, plate, shell and integration of it into a global stiffness matrix. But I find it but of an obscure on how to integrate the constraint matrix into the...

You should get bullet collection where the sequence of bullets is important, for example from the 1st box pick one bullet, from 2nd box pick two bullets, from 3rd box pick 3 bullets... from 10th box pick 10 bullets. So totally you get 10*11/2=55 bullets collection, that means it should be...

Dear All, Your help really will be appreciated.

Thank you all for replying, As I see one way or the other I always end up in the LAPACK library (eispack,arpack, blas, etc..). It seems that this package is robust in every way which can solve most ODEs and PDEs in maths. Please confirm if can I achieve the solution of the equation...

The books also mention that we can use the eigenvalues as a part of the solution techniques, but I don't know where it's been introduced in that overall process, partially or as whole process relies simply on eigenvalues. I wonder, is that all solution process for ODEs is suitable for the...