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.

Computing second derivative with deformed Geometry

Please login with a confirmed email address before reporting spam

Hello,

I'm trying to figure out how set the second derivative of a boundary as a variable, but the mesh is changing so it has to be re-calculated every time step. Is there some way to have the second derivative along the boundary be recalculated every time the mesh is updated?

In addition, I'm also having trouble even plotting the second derivative, I can plot (in axis-symmetrical) z(r), a Gaussian, but when I try to plot 'd(z,r)' it gives me a constant 0, which I know isn't right.

-Ben
EDIT:
I was able to plot a first derivative with dtang(z,r), but if I did dtang(dtang(z,r),r) then I get a constant 0 value again.


0 Replies Last Post 2016年6月13日 GMT-4 14:45
COMSOL Moderator

Hello Ben Cutler

Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.

If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.