Pro/MECHANICA

[kcmsa]

Has anyone run across any publications with some real world examples? Preferably using MECHANICA as the solver. This would really be helpful for a new user in setting up constraints and boundry conditions specifically for the MECHANICA interface.

X-)

Thanks,
Ken

 

[tsankar]

Hi,
Have you tried the PTC web site?. Have not come across many using Mechanica. If you are a Pro/E user, using Mechanica would be advantageous especially in the integrated mode . But the software has many limitations (no good way of controlling the mesh in the integrated mode,limited elements etc-Iam referring to the 2000i version).

If I come across any material I will let you know.

Good Luck,

TS

 

Hi,
have you tried the ProUser web site? There you will find some hints or better try the ProUser newsgroup 'sim' at the newsserver 'news.prouser.net'.

For a new user the book 'Pro/MECHANICA Structure Tutorial, Release 2000i (A Click-by-Click Primer)' will be helpfull.

I'm using mechanic for 2 years now and can't see the limitations which TS has mentioned. But I'm referring to the independent mode of mechanica.

gk

 

[tsankar]

Gklocmann,
I might have been wrong in mentioning that Mechanica is limited. Since it uses p-elements, mesh refinement nay not be really required. But I have been facing problems in using spring elements.
1.)I have not been able to appreciate the true function of the spring orientation property. A similar property is also required for beams also(for defining the orientation of the beam action Coordinate system w.r.t the global coordinate system)Can you help me on this?.Also I find that only the independent mode helps in defining the Autogem settings(like type of element and maximum aspect ratio).

2.) Rigid links are not available in Mechanica 2000i. Even though it is available in 2000i2 it does not help in connecting a point mass to a shell or a solid(I think MSC/Nastran allows this-Please correct me if Iam wrong). I find this a problem since I have to model a beam of high stiffness and in case the beam is connected to a solid i have to constrain the rotational DOF at the point it meets the solid( Provided Iam not using more than one beam to connect the point mass to the solid in which case the arrangement of the beams may automatically cancel the rotational DOF).


Can you help me on this?.


Thanks,
TS

 

Hi tsankar,

these are a lot of questions, i will try to answer them one by one.

1.) Orientations of springs and beams

In Mechanica you are always defining the local CS for these elements. The local x-axis is by default orientated in beam or spring direction. So have only to define the direction of the y- (Version 2000i) or z-direction (Version 2000i2). These directions are by default perpendicular to the beam or spring axis. So if you define your beam orientation w.r.t the GCS, Mechanica choose an orientation of the y-(or z-axis) which is perpendicular to the beam axis.

If you want to be sure in which direction the local y-axis is pointing, define an local CS at the beam and define the orientation w.r.t LCS.

2.) You can use the AutoGEM settings even in the integrated mode, there are no differences to the AutoGEM settings in the independent mode.

3.) Rigid links in Mechanica can only connected to points, curves and surfaces. So you are right. But the point mass is defined at a point, an if this point is connected with a shell or solid you can also connect a rigid link with this point.

I do not understand how you want to constrain the rotational DOF at the point where the beam meets the solid. Even if you use a rigid link, you have to connect this link with a minimum of 2 points at the solid.

If I would use a beam of high stiffness, then I would create a shell element on the face of the solid. By this shell element, the rot. DOF is constrained.

In Mechanica 2000i2 I would use a rigid connection which is connected a the point mass (as described above) and connected at 2 or more points of the solid. This has the same effect as using two ore more beams to constrain the rot. DOF.

regards gk

 

[tsankar]

Gklockmann,
Thanks a lot. Being a relatively new user of Mechanica many questions arise . My problem was that of a equipment base to which i had to connect a point mass(which was located at a certain distance above the base).I had used beams to connect it to the base (in 2000i). I understand from your explanation that I can use rigid links in the place of beams if I use 2000i2.(I hope Iam correct).Also thanks for the tip about creating a shell at the face of the solid.

Regards,

TS