Convergence

Altair Forum User

How do I know the convergence of mesh size in my model?

Is there a method to know if the mesh has converged?

Altair Forum User

Hi Hemant,

Mesh density and solution convergence are closely related and the factors which determine that relationship can be controversial.  In an effort to meet specific time and accuracy requirements, trade-offs involving modeling time, accuracy, computation time, and cost must be made.

 The correct mesh, from a numerical accuracy standpoint, is one that yields no significant differences in the results when a mesh refinement is introduced. Mesh refinements must accurately represent the problem in question if they are to be used in the analysis. Mesh refinements by simple splitting of elements can be misleading unless the newly created nodes conform closely to the original geometry. As refinement progresses, the original element selection must retain its significance. For example, a shell model can be refined to the point that it loses its validity in the area of interest, creating a need for a solid element model.

 

Please go through our free ebook on Practical Aspects of Finite Element Simulation (a Study Guide) which can be downloaded form  http://www.altairuniversity.com/free-ebooks-2/free-ebook-practical-aspects-of-finite-element-simulation-a-study-guide/. This contains all the basic theoretical concepts of Finite Element Analysis.

 

Q.Nguyen-Dai

For evaluating 'Convergence' you have to perform several analysis by refining element size.

Warning: not all refinement could give you 'convergence' goal.