Hello everyone, I'm having some big problems trying to solve a finite element method problem for my class. I am trying to determine a stiffness matrix for a problem I was assigned and this requires me to double integrate an 8x3 matrix, a 3x3 matrix, and a 3x8 matrix. I get mathcad to perform the matrix multiplication to give me an 8x8 matrix, even though it says the symbolic value is too large to display. However the issue is, I cannot assign a variable to the result that I am got, I do not understand how to get this to work, when I know mathCAD should be able to do the computation. Below attached is the exact solution to what I am talking about. Please help!
However, your integrals don't seem to converge.
Reason for this is that the integrand BEB is an 8 x 8 matrix. It may be possible to evaluate that integral symbolically, but I had not enough patience to wait for the calculation to finish (if it ever would).
One way to get a numerical result is to do the calculation element wise. Vectorization does not work here, so I used range variables. Actually the Gamma values would be dependent on eta but with the given values of the x's and y's the Jacobian and the Gammas are independent from eta, so I did not change anything here.
Are you sure that you expected an 8 x 8 result here?
BTW, you should avoid copying an pasting numeric result but rather use variables
