• Registered: 16-10-2010
  • Posts: 407

Topic: ActivityLTF and its meaning

Hi all

I'm writing to ask some info about activityLTF, for which I didn't found documentation.

By gathering info directly from code and here in the forum, I understood that this command, when associated to an element, can activate/deactivate its presence in the model for the current time step. It's active when the associate time function returns a value different from 0.

I tried to make a model made by 2 beams; I want beam 2 to be activated at t=4.

I get nan(ind) in results.
Did I misuse something? please find model attached.

Post's attachments

testCS.in 1.46 kb, 3 downloads since 2020-04-18 

You don't have the permssions to download the attachments of this post.

2 Reply by bp

  • bp
  • Administrator
  • Offline
  • From: Prague, Czech Rep.
  • Registered: 02-03-2007
  • Posts: 1,026

Re: ActivityLTF and its meaning

Hello,
the problem is that when your element #2 is inactive then the node #3 is not connected to any element and is free to move. You have to remove all DOFs of this node when not connected to any active element.
Borek

bp's Website

  • Registered: 16-10-2010
  • Posts: 407

Re: ActivityLTF and its meaning

Thanks for your reply. I believed that nodes alone were removed with associated elements, now it works.

  • Registered: 16-10-2010
  • Posts: 407

Re: ActivityLTF and its meaning

Borek, the model works only if I apply a BC to node 3, which remains free until beam no.2 is added. In this way, I'm unable to remove the BC after t=2.

Is there a way to remove or make inactive the BC applied to node 3 from t=2 on?
thanks in advance

Post's attachments

testCS.in 1.54 kb, file has never been downloaded. 

You don't have the permssions to download the attachments of this post.

5 Reply by bp

  • bp
  • Administrator
  • Offline
  • From: Prague, Czech Rep.
  • Registered: 02-03-2007
  • Posts: 1,026

Re: ActivityLTF and its meaning

Boundary condition has optional isImposedTimeFunction keyword to achieve exactly this. See http://www.oofem.org/resources/doc/oofe … ode44.html

Borek

bp's Website