Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.
In comsol is it possible to set a BC for a couple of seconds and then release it?
Posted Feb 24, 2020, 7:31 a.m. EST Version 5.5 2 Replies
Please login with a confirmed email address before reporting spam
As states i am running a time-dependent simulation in solid mechanics. I want to set a prescribed displacement to zero for the first 0.05s and then release it to free. Is there any way that I can do it?
Please login with a confirmed email address before reporting spam
Hi Boyue,
You should be able to get such an effect by adding a Prescribed Displacement node and choose the General notation option. Then add an expression for the H matrix (really an isotropic scalar value here) like
1*(t[1/s]<0.05)
where t is the time (made dimensionless by [1/s]). When then time is less than 0.05 s, the expression becomes 1, and the displacement is set to 0. When the time is 0.05 or more, the equation for the prescribed displacement is essentially 0 = 0, which does not add any constraint, so the boundary becomes free.
Best regards,
Magnus Ringh, COMSOL
Please login with a confirmed email address before reporting spam
See also this blog post :
https://www.comsol.se/blogs/how-to-make-boundary-conditions-conditional-in-your-simulation
-------------------Henrik Sönnerlind
COMSOL