Field output transformation doesn't work?
Field output transformation doesn't work?
(OP)
Hi!
My model is as follow:
3D solid, revolved, C3D8 elements, material: steel.
I am trying to transform the field output of my model into a cylindrical coordinate system with CAE.
Therefore I create a news CSYS in the visualisation module and in "result options" I choose transformation -> user-defined.
This seems to work fine with the stresses, however the strains are not converted correctly: the model and load are axisymmetric, so the strain in theta direction (S22 in the new CSYS) should be constant, but it isn't.
As this didn't work I tried out a lot of other ways to transform my results: with *orientation in **part I got the same results.
The only way that works is to use *orientation in material, but I don't like this solution because my material is steel and therefore isotropic. Why should I use material orientation then!?
Does anyone know why the transformation in the visualisation module doesn't work as I want? (Or what I am doing wrong?)
Thanks alot in advance,
Gael
My model is as follow:
3D solid, revolved, C3D8 elements, material: steel.
I am trying to transform the field output of my model into a cylindrical coordinate system with CAE.
Therefore I create a news CSYS in the visualisation module and in "result options" I choose transformation -> user-defined.
This seems to work fine with the stresses, however the strains are not converted correctly: the model and load are axisymmetric, so the strain in theta direction (S22 in the new CSYS) should be constant, but it isn't.
As this didn't work I tried out a lot of other ways to transform my results: with *orientation in **part I got the same results.
The only way that works is to use *orientation in material, but I don't like this solution because my material is steel and therefore isotropic. Why should I use material orientation then!?
Does anyone know why the transformation in the visualisation module doesn't work as I want? (Or what I am doing wrong?)
Thanks alot in advance,
Gael





RE: Field output transformation doesn't work?
corus
RE: Field output transformation doesn't work?
the transformation in Abaqus/Viewer converts correctly.
When your model and load is axisymmetric, then use a
2D-axiasymmetric model as corus advised.
Tamlin
RE: Field output transformation doesn't work?
The model (a contacting part) and the load are not axisymmetric in the following steps, which are the important steps, that's why I didn't use the 2D axisymmetric elements.
Unfortunately I don't think I can use the "2D axisymmetric with non axisymmetric load" elements (CAXA) here either. The documentation for these elements is not really helpful but from what I understand it doesn't seem possible.
I checked the stresses and strains in the first (axisymmetric) step to verify that the conversion was correct, and that's how noticed something went wrong.
Yes I guess the conversion works correcty in CAE, but could someone please tell me what I am doing wrong, or how it should be done step by step so I can verify what I do?
thanks again,
Gael
RE: Field output transformation doesn't work?
RE: Field output transformation doesn't work?
It is a simple C3D8 cylinder under axisymmetric load, with axisymmetric mesh, nothing else. (no contact)
As you say Drej, after the transformation into a cylindrical (r,theta,z) CSYS (origin in the center), I expect the following results:
concentric r,theta and z stresses/strains.
What I get:
-concentric r,theta and z stresses.
-a concentric z strain.
So far so good. But I also get
-non concentric r and theta strains. (with differences ~50% between min and max. value)
Is it a definition problem, an error or am I expecting wrong results?
In the Abaqus/CAE visualisation module you can use the Symbol plot to plot the tensor direct components. The components are as I expected after the transformation (1 is radial etc.)
I would really appreciate it if someone could try out the result transformation on a simple model as I did, and tell me the result.
Thanks alot,
Gael