Hello, I tried a simple linear elastic analysis and added a couple of spring constraints to a reference node. It appears to me:
spring constraints are always assumed to connect to the ground (i.e. the spring is fixed at one end), whereas I’d rather have the spring be connected between two nodes;
I am unable to obtain the reaction force in the spring.
Can somebody confirm and explain how I get the spring constraint reaction force ?
Also, I fail to see any possibility to include rotational springs, although a node is endowed with rotational DOFs. Therefore I had to apply a BC and block those rotation. Personally I feel some consistency may be missing here. Is it a problem with Prepomax not supporting the feature or it is altogether missing in Calculix ?
Thank you,
Andrea
Got it, clear. But unless I am much mistaken, my spring is attached to a reference node and there is a forum that I skimmed through which discusses the fact that ref nodes have variable node numbers (each time the model is run) and it is therefore hard to request at the output stage that particular node reaction force, that is basically what I need.
My desire would be to have all the reaction forces collected in one place at post-proc, including the springs, as a form of output from calculix.
Leaving aside, of course, the option to manually click the node in prepomax, which is also difficult because, if I am correct again, reference node disappear from the model at post processing.
Any good idea ?
On a lesser note, the fact that rotational springs are not supported is very surprising, as I cannot see any technical difficulty more than reproducing linear spring code yet with respect to rotational degrees of freedom.
Was this left behind in Calculix for some reason I fail to understand ?
If the spring is attached to the reference point of a rigid body, you can request the RF output for it by switching the Region type to Reference point name.