1. Abaqus Users (Commercial Finite Element Code) http://comments.gmane.org/gmane.comp.mathematics.abaqus.user/6152
Abaqus Users (Commercial Finite Element Code)
larspmik | 16 Jun 2005 16:51 headers
RETURN
Return to
visualizing of SDV from UEl using UMAT
gmane.comp.mathematics.abaqus.user.
I am writing a user subroutine (UEL) to ABAQUS version 6.5-1. What is
the easist way to visualizing the results using CAE.
PROJECT WEB
PAGE
I visualize the displacement by overlaing the UEL with a soft linear
Abaqus Users (Commercial
elastic element where the displacements is interpolated with similar
Finite Element Code)
shapefunctions. An example for one element with a overlaied soft
element is shown in the bottom of this email.
SEARCH
ARCHIVE My question is how to visualize the other state variables
(stresses, strain, plastic strain ...) from the UEL using the contour
plots tools etc. in CAE.
My idea is to change the soft overlaied elastic element to a soft
elastic element using a Umat subroutine. This overlaied element can
LANGUAGE then be used to save the SDV from the UEL. Thereafter the CAE can be
Change language used to plot
the SDV from the UMAT model. Some book-keeping is required regarding
the UEL <-> UMAT numbering in order to save the SDVs from the UEL to
OPTIONS
the SDV's in the soft overlaied Umat material.
Current view: Threads only /
Showing only 20 lines / Not
hiding cited text. Has someone done something similar or have an other way to do
Change to All messages, whole
something similar?
messages, or hide cited text.
Post a message
Lars
NNTP Newsgroup
Classic Gmane web interface
RSS Feed !!!!!!!!!!!!!!!!EXAMPLE OF OVERLAIED ELEMENT !!!!!!!!!!!!!!!!!!!!!
List Information *user element, type=u1, nodes=8, coordinates=2,properties=11,i
About Gmane properties=0, variables=126
** variables= n of state var in each element
** 1,2,..!!!NOT = 10 !!!
(Continue reading)
Permalink | Reply | Repo rt this as s pam
Fernando | 17 Jun 2005 18:43 headers
Re: visualizing of SDV from UEl using UMAT
Hi Lars,
> What is the easist way to visualizing the results using CAE.
>
> My question is how to visualize the other state variables
> (stresses, strain, plastic strain ...) from the UEL using the
> contour plots tools etc. in CAE.
>
> My idea is to change the soft overlaied elastic element to a soft
> elastic element using a Umat subroutine. This overlaied element can
1 of 3 28-12-2012 11:40

2. Abaqus Users (Commercial Finite Element Code) http://comments.gmane.org/gmane.comp.mathematics.abaqus.user/6152
> then be used to save the SDV from the UEL. Thereafter the CAE can
> be used to plot the SDV from the UMAT model. Some book-keeping is
> required regarding the UEL <-> UMAT numbering in order to save the
> SDVs from the UEL to the SDV's in the soft overlaied Umat material.
You don't need to overlay a dummy element in order to visualize
displacements (deformed vs undeformed plots), because displacements
are nodal variables that are stored at the nodes. If you want to
contour the deformation tensor or some other strain measure, then you
need to have information about integration points, and here is when it
gets tricky.
ABAQUS does not help you to plot you UEL results, just because nobody
can predict how many nodes or integration points your UEL might have,
and much less the locations of the integration points or the exact
form of the shape functions. So there is just no way for ABAQUS/Viewer
or /CAE to display your results or calculate derived variables. There
is a way out, though: the scripting interface, or alternatively the
c++ API.
(Continue reading)
Permalink | Reply | Repo rt this as s pam
Lars Pilgaard Mikkelsen | 17 Jun 2005 22:34 headers
Re: visualizing of SDV from UEl using UMAT
Hi Fernando,
Thank you for your explanation. As my UEl regarding the shape
functions for the displacements, the possition of the nodes and the
integrationspoints are similar to a standard 8-noded plane element I
suppose your suggestion is quite advantageous avoiding me using a
dummy element. (I am using the dummy element now in order to connect
the nodes in a correct way on the plot for the deformed mesh.)
Nevertheless, how do you do it. I can not find a description in the
ABAQUS manual:
1) How do I store my statevariables (svars) in SDV fields?
I suppose it is not the same as the svars variables saved used in the
UEl-routine. Can I do this directely from my Uel-routine using a
subroutine call?
2) How does I change the element type from U1 to a cpe8 element in my
odb-file. Is it by a python script and is such a script available from
the ABAQUS distribution.
3) Do I reshape the SDV into stresses, strains, ... in a simliar way
again using a python script.
Thank you very much,
Lars
--- In ABAQUS <at> yahoogroups.com, "Fernando" <atila <at> u...> wrote:
> You need to store your UEL results in SDV fields, which are stored in
> the *.odb file and can be accessed by the script. Then all you need to
2 of 3 28-12-2012 11:40

3. Abaqus Users (Commercial Finite Element Code) http://comments.gmane.org/gmane.comp.mathematics.abaqus.user/6152
(Continue reading)
Permalink | Reply | Repo rt this as s pam
Fernando | 20 Jun 2005 10:13 headers
Re: visualizing of SDV from UEl using UMAT
Hi Lars,
> Nevertheless, how do you do it. I can not find a description in the
> ABAQUS manual:
>
> 1) How do I store my statevariables (svars) in SDV fields?
> I suppose it is not the same as the svars variables saved used in
> the UEl-routine. Can I do this directely from my Uel-routine using
> a subroutine call?
In a user element, state variables and field variables are treated the
same, so internal variables for your element and externally visible
results, such as stresses, must all be taken into account. Say your
element has an internal state variable to keep track of something
(damage for instance), and that you want to output stresses, then you
need to have 7 variables per integration point. If you have 8
integration point, your SVARS field in the input file should be 56.
The order in which you define them is of course up to you.
> 2) How does I change the element type from U1 to a cpe8 element in
> my odb-file. Is it by a python script and is such a script
> available from the ABAQUS distribution.
To do that, you need to study the ABAQUS Scripting manual, everything
is explained in depth there (and also how to do the same in c++)
> 3) Do I reshape the SDV into stresses, strains, ... in a simliar
> way again using a python script.
Again, check the Scripting manual, it's easy to follow and has useful
(Continue reading)
Permalink | Reply | Repo rt this as s pam
Gmane
3 of 3 28-12-2012 11:40