Mesh density definition

[Geros]

Good morning

I would like to ask you, theoretically, how to you pick a mesh density in one model.What I mean is how do you know how many nodes and elements is right to have in your model..
Thank you..

 

[rb1957]

any text should tell you ...
1) start with a mesh that captures the geometry, refine the mesh where you expect stress gradients;
2) refine the mesh again
3) see if the results change significantly
4) if signicant change return to 2), if not exit.

another day in paradise, or is paradise one day closer ?

 

[Geros]

Thank you for your response..
But my question is if there is way to calculate the amount of elements needed without meshing the model first.

 

[rb1957]

no

another day in paradise, or is paradise one day closer ?

 

[corus]

You can get a feel for how many elements you need by running a simple model and experimenting with different mesh sizes to see how they converge. Typically for cylinder walls I'd use a minimum of 4 quadratic elements through the thickness, maybe more depending on the problem. There's no method for 'calculating' the elements as such, as a lot depends on the type of loading, or stress features there may be.