Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

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.

total drag/reacf()

Please login with a confirmed email address before reporting spam

Hello,

I have been reading a few threads up to now, but none of the really helped me along with my problem.
As others, I would like to get the drag of an object. I am able to do so with the reacf() operator, which is set on "ON" by default. So I just need to add the right boundary and plot it? How do I do this?
The same issue is dealt with in the tutorial "Flow over a circluar cylinder" right? Maybe the tutorial could help? But I am not able to find this tutorial anywhere.

I'd really appreciate very kind of help on this topic.

Felix

4 Replies Last Post 9 avr. 2012, 15:03 UTC−4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 9 avr. 2012, 04:10 UTC−4
Hi

you should use a more mature version, many things were not yet implemented in the 4.0 first issue after the v3.5-> 4 (r)evolution ;)

I often use polar plots to look at forces versus direction, but I'm not even sure polar plot is in v4.0

--
Good luck
Ivar
Hi you should use a more mature version, many things were not yet implemented in the 4.0 first issue after the v3.5-> 4 (r)evolution ;) I often use polar plots to look at forces versus direction, but I'm not even sure polar plot is in v4.0 -- Good luck Ivar

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 9 avr. 2012, 04:54 UTC−4
Hi Ivar,

thank you for your reply. So I will be trying to get my hands on a newer version at my college. But since I am still on novice level in Comsol, maybe you could tell if I am doing this right. Because there is no reacf used in the cylinder flow file .
-Add a new "Line Integration" in "Derived Values"
-Select Outlet boundary and type in "reacf(u)" as Expression --> hit Evaluate in new Table
-Create new 1D Plot Group
- Add Table Plot --> Select Table Nr of the reacf table
- Hit "Add Plot Data to Report"
Now I should be able to able to export the data...right?

Thanks in advance
Hi Ivar, thank you for your reply. So I will be trying to get my hands on a newer version at my college. But since I am still on novice level in Comsol, maybe you could tell if I am doing this right. Because there is no reacf used in the cylinder flow file . -Add a new "Line Integration" in "Derived Values" -Select Outlet boundary and type in "reacf(u)" as Expression --> hit Evaluate in new Table -Create new 1D Plot Group - Add Table Plot --> Select Table Nr of the reacf table - Hit "Add Plot Data to Report" Now I should be able to able to export the data...right? Thanks in advance

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 9 avr. 2012, 07:45 UTC−4
Hi

to export you should normally be able to extract already at the level of the "data set" integration and at table level. Check right clicks on these nodes

--
Good luck
Ivar
Hi to export you should normally be able to extract already at the level of the "data set" integration and at table level. Check right clicks on these nodes -- Good luck Ivar

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 9 avr. 2012, 15:03 UTC−4
Hi Ivar

I found the tutorial for the cyclinder flow example. I think I get it now.
The 4.0 Version hasn't got Polar Plots...

Thank you
Hi Ivar I found the tutorial for the cyclinder flow example. I think I get it now. The 4.0 Version hasn't got Polar Plots... Thank you

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.