Boundary Conditions without SPC - composites
Altair EmployeeDear,
I am making a model of a carbon chassis in hypermesh. I apply my suspension loads at the suspension points. How can I make my model without using SPC's as my boundary condition? The only logic place to make use of the SPC is at the suspension pick up points. But I cannot fix these because then it becomes impossible to check if my laminate is strong enough. How can I apply boundary conditions without using SPC?
Kind Regards,
Answers
-
Hi,
Create a dummy SPC outside the model.
for example create a temporary node which is out side the model (not associated with model/assembly) and create a SPC on this node.
Use this dummy SPC to create a load step and run the analysis
0 -
Hi Thank you for answering.
I have included my model in attachment. I use this model to get to the model I want to use eventually. As mentioned before I want to apply my loads without fixing this point in space ( because applying a constraint would not be the same is in reality). You told me to use a dummy variable. I didnt quite understand how to do this on my model. As you can see I created rigids to simulate the brackets where my loads act.
Do you still advice me to use a dummy variable? Or should I go to inertia relief? Which I tried by using the same boundary conditions as you see in the model, but then assigned to suport1. This gave me an error 23 (SID 1 used on Case Control data SUPORT1 is missing in bulk data).
Another thing I wanted in my model is the failure index. I filled in everything required for the failure criteria, but I cannot see it in my results? The things I filled in are:
Failure criteria: Hoffman and interlaminar shear stress (sb)
the material card with xt, xc, yt, yc and S
And I activated the global_output_request
Thank you for helping me,
0 -
Hi,
If there is no support the structure will be stiff eventually.
I think you can do a inertia relief instead of using a dummy SPC.
From 13.0 CFAILURE is used to output failure index, composite stress, etc... Refer to the belo forum post for details:
0 -
Dear,
I have been experimenting with the inertia relief method. I've got the following problem, in the loadcase at which I make use of this method I get a large displacement in my CROD elements. I have no idea what the reason for this is, I already checked for free 1D elements and nodes. Did I do something wrong in setting the model up?
0