Different results by mesh size 1

[abaqus7877]

Hello

I am pretty new and just trying to solve simple cantiliever beam.
But, Everytime I change the mesh size or element type, the results are also changed significantly. I don't see what's wrong. Is it normal? Is there any general rule to make reasonal mesh size or density? Any feedback would be very appreciated.

Thank you!
J

 

[abaqus7877]

I have attached the captures. Please help me. I am stuck.

Thank you.

 

[DanStro]

It looks like you BC is only being applied to only two nodes out of the 12 that you have with the higher density mesh. That's not necessarily why your seeing the dramatic change but it is some of it.
HTH.
Dan

Han primo incensus

 

[abaqus7877]

Thank you so much for the post, Dan.

I tested several cases (different Load types, different BC types,....). Whatever the cases, the higher the mesh density, the higher the stress level. I don't know which makes more sense.

Can you please do this simple test? If you don't see this on your test, definitly something wrong on my test.

Thank you so much again.
J

 

[corus]

I suggest you do the problem yourself but this time make sure you have the correct BCs in order to make a valid comparison between models, and then compare the results with a hand calculation.

 

[Flo67]

Hello,

The results depend on the mesh, if the mesh isn't well adapted. For example, for this kind of simulation, you need at least 4 elements C3D8R (Hexa) im the thickness. If you use tetrahedral elements (C3D10), 2 may be sufficient.

In this case, you can compare the simulated deflection or force, with the theoretical solution to verify your mesh.

Regards