Export Contact Pressure as xy-data

[catrueeb]

I have a nonlinear simulation with one rigid surface pressing on a soft material. Now I would like to plot the contact stress or (even better) the contact force on the SURFACE of the soft body (it is one surface)in matlab. Therefore I tried to export the force values as en xy data file. I have two issues:
1) I can create an element nodal xy object for the contact force / stress. Is there a way to represent this data as unique nodal or even with x-y-z coordinates?
2) When I select the surface it creates an x/y data object for every element, but I want to show the forces for all nodes on the surface in one object.

What is the easiest way to export the contact force data to matlab and plot it in there? Thank you very much already!

 

[Mustaine3]

Why don't you request CFN or similar variables as History Output for an interaction?

 

[catrueeb]

I need to output the contact force on every element on a specific surface. In the history output I can only find total contact force... I am still trying to find a more comfortable way than exporting the contact stress values and calculate the forces from them.

 

[Mustaine3]

Take a look at CFORCE (leads to CNORMF) and CNAREA. This is nodal output at the contact master face. The variable COORD can show the nodal coordinates. All this can be exported with Report -> Field Output.

 

[catrueeb]

Thank you very much. It is a pitty the report puts the COORD variable in a separate table instead of an additional column for the stress values. Seems I have to do some Matlab work to assign the nodal stress values to their coordinates.
One more thing: Are the "element-nodal" values the conributions of the nodes to the respective element or do I have to divide the values by the number of adjacent elements? I am a bit confused how to conclude to the force/element from force/node and the difference between unique nodal and element-nodal.

 

[Mustaine3]

Yes, 'Element Nodal' treats every element separately, so you should check how many elements you have per node.
'Unique Nodal' has directly the nodal results or the values averaged at the nodes.