Relationship between number of nodes and the number of equations solve

[jwshelt]

What is the relationship between the number of nodes and the number of equations solved (e) for a structural FEA problem?

 

[mloew]

jwshelt,

It will depend on the number of degrees of freedom (DOF) for each node and the element connectivity (how the nodes are shared among adjacent elements. A good thread to look at for references on FEM/FEM basics is: thread727-22036. Best regards,

Matthew Ian Loew

 

[zuardy]

yes, i agree with MLoew. The number of equations solved (e) for a structural FEA problem is equal to the size of Stiffness matrix, a square matrix, where is it's size depend on the number of DOFs. Normally the number of DOFs is the sum of Nodes multiplied by DOFs at each nodes.

cheers

 

[idly123]

It is not necessary that u need to solve for all the DOFS..u can always condense out internal DOFS in which case the number of equations to be solved depends on the number of such internal DOFS exsisting. Raj
Structural Engr.