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.

Deformated mesh and Von Misses stress at the same plot

Please login with a confirmed email address before reporting spam



How can I obtain Deformated mesh and Von Misses stress at the same plot?


Please help i gonna die if you dont help me..............

5 Replies Last Post 2010/05/12 12:27 GMT-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 2010/05/12 9:23 GMT-4
Hi,

come on

PC and computing stress is not good for your health;

What about trying the tick mark "plot parameters - deformed shape"

but it depends also on your model, if you are using "deformed frame on", you might get the douple of the deformation ;)

Have fun Comsoling
Ivar
Hi, come on PC and computing stress is not good for your health; What about trying the tick mark "plot parameters - deformed shape" but it depends also on your model, if you are using "deformed frame on", you might get the douple of the deformation ;) Have fun Comsoling Ivar

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2010/05/12 10:01 GMT-4

Actually i know how obtain the deformated shape....

What i want to know is how obtain the DEFORMATED SHAPE and the VON MISSES STRESS at the same plot
Actually i know how obtain the deformated shape.... What i want to know is how obtain the DEFORMATED SHAPE and the VON MISSES STRESS at the same plot

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2010/05/12 10:02 GMT-4


Please help me..............PLEASE
Please help me..............PLEASE

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2010/05/12 10:07 GMT-4

Excuse me DEFORMATED MESH and von misses stress at he same plot
Excuse me DEFORMATED MESH and von misses stress at he same plot

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 2010/05/12 12:27 GMT-4
Hi

Cool down, and do not spam the forum ! the OWNERS of the site migh well decide to exclude you for a while !


You seem to be too stressed there, I assume examen deadline or so, but are you not forgetting to THINK correctly and adding in a lot of errors like that ?

Anyhow, above what I can decide, I do have also some masters: the one high up there, my boss, my whife and kids AND the Swiss Railroad system, no way to enter a train 2 seconds after the departure time, because it's simple no longer there, and I'm not ready to wait an extra hour for the next one, unlucky for you tonight ;) Be patient I'll continue during the travel ...



Anyhow I do not 100% understand what you want, as it seems contradictory:

I assume you have a structural case x,y,z with displacements u,v,w (dependent variables). Pls suppress what is too much to get to your dimensions.

So you solve for u,v,w, and therefore get also the 6 stress tensor components sx,sy,sz,sxy,sxz,syz, von Mises is just an good average of the 6-S'. But if u,v,w are really defines at the nodes (and inherited to the edges, boundaries=surfaces, but not as such on the volumes/subdomains), the stress is ONLY defined as an average over the element = volume = subdomain. Now you can also define an average displacement for the elements hence a subdomain average value, but it's slight more complex than for the surface and edges. This is taken care of by COMSOL.

That is why you see u,v,w under Postprocessing "subdomain" and under "boundary" (as well as edges and points), but you will not find stress values under boudary=surface plots.

So how to overlap both ?

I do not really know: if you do not like to use the "deformed shape" to show the deformations and the von-mises on the subdomain (what you see is the average stress of the elements along the surfaces, except if you use a slice plot). If you select subdomain plot of von Mises and surface plot of deformations then you will have two (2) overlapping "Rainbow" plots and you will not see anything usefull, I believe.

Perhaps by showing one as a contour plot could help.

So to make a long story shorter, I'll advise you to think carefully over what you want, then to go over the options COMSOL is proposing under postprocessing, you will gain time for your following plots.

Well my travel time is over so I must cut short here, anyhow I do not have much more to add.

A last thing: yes there is a difference between deformed mesh (meshing) and shape (deformed shape u,v,w), you select the frame to plot on the "general" tab of the postprocessing, if you have several frames.
Again, if you add ALE or turn "deformed frame on" under "physics properties", then you must decide about everywhere if you want to refer to the original mesh or the deformed mesh, it's not always giving the same results ;)


Have fun Comsoling, and destress ;)

Ivar
Hi Cool down, and do not spam the forum ! the OWNERS of the site migh well decide to exclude you for a while ! You seem to be too stressed there, I assume examen deadline or so, but are you not forgetting to THINK correctly and adding in a lot of errors like that ? Anyhow, above what I can decide, I do have also some masters: the one high up there, my boss, my whife and kids AND the Swiss Railroad system, no way to enter a train 2 seconds after the departure time, because it's simple no longer there, and I'm not ready to wait an extra hour for the next one, unlucky for you tonight ;) Be patient I'll continue during the travel ... Anyhow I do not 100% understand what you want, as it seems contradictory: I assume you have a structural case x,y,z with displacements u,v,w (dependent variables). Pls suppress what is too much to get to your dimensions. So you solve for u,v,w, and therefore get also the 6 stress tensor components sx,sy,sz,sxy,sxz,syz, von Mises is just an good average of the 6-S'. But if u,v,w are really defines at the nodes (and inherited to the edges, boundaries=surfaces, but not as such on the volumes/subdomains), the stress is ONLY defined as an average over the element = volume = subdomain. Now you can also define an average displacement for the elements hence a subdomain average value, but it's slight more complex than for the surface and edges. This is taken care of by COMSOL. That is why you see u,v,w under Postprocessing "subdomain" and under "boundary" (as well as edges and points), but you will not find stress values under boudary=surface plots. So how to overlap both ? I do not really know: if you do not like to use the "deformed shape" to show the deformations and the von-mises on the subdomain (what you see is the average stress of the elements along the surfaces, except if you use a slice plot). If you select subdomain plot of von Mises and surface plot of deformations then you will have two (2) overlapping "Rainbow" plots and you will not see anything usefull, I believe. Perhaps by showing one as a contour plot could help. So to make a long story shorter, I'll advise you to think carefully over what you want, then to go over the options COMSOL is proposing under postprocessing, you will gain time for your following plots. Well my travel time is over so I must cut short here, anyhow I do not have much more to add. A last thing: yes there is a difference between deformed mesh (meshing) and shape (deformed shape u,v,w), you select the frame to plot on the "general" tab of the postprocessing, if you have several frames. Again, if you add ALE or turn "deformed frame on" under "physics properties", then you must decide about everywhere if you want to refer to the original mesh or the deformed mesh, it's not always giving the same results ;) Have fun Comsoling, and destress ;) Ivar

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.