Contact problems

[CassandraW]

I'm trying to solve a very simple problem in Abaqus as a step towards validating and creating the far more complicated model I need to solve.

I have two perpendicular half cylinders, they are each 1000mm long with a radius of 250mm. A fixed constraint is applied to the base of one cylinder. A concentrated load is applied to the centre of the top of the second cylinder and zero displacement in any direction but the load direction constraints applied to the end faces. At the contact area the mesh sizing is 0.2mm which from my hand calculations should give 20 elements over the contact patch. The analysis is Static, General and the contact is set to not adjust the nodes and to attempt 3D smoothing when applicable.

However the results I am obtaining give a point contact with 1405GPa maximum contact pressure which is significantly in excess of what my hand calculations predicted.

 

[Mustaine3]

Your unit system does not fit. You model dimension is in mm, but your material data seem to be in m.

The radius of the cylinders is 150mm instead of 250mm.

 

[CassandraW]

Yeah lets call the radii a typo not me failing to double check the word document where I had this all written down.

I'll correct the Young's modulus and density when I go back to work tomorrow. For a 8000kg/m3 density in to consistent units it would be 8e-3 tonne/mm3?

 

[CassandraW]

Thank you.

Changing to consistent units is now giving the right stress and contact pressure distributions.