[jcamilleri]

Hi all,

I am trying to model a pressure transducer on the bottom of a wedge to measure the surface average pressure on the transducer surface. I created a sketch of the pressure transducer in 3D CAD (a circle with a diameter of 9mm) on the plane of the wedge surface and extruded the sketch (two way symmetric extrusion with body interaction set to imprint). The problem is that when I try to mesh the domain the shape of the pressure transducer changes to a triangle. The cell size in the region of this imprint is 1.25 mm (so the tranducer would occupy roughly 7 cells.

Some other options I tried with no luck were: increasing the diameter of the transducer to twice its value to see if the problem is because of the small diameter, applied further refinement (0.625mm) in the region of the transducer using a volumetric control and changing the basic curvature (#pt/circle from 36 to 72 and 144).

Any ideas?


Regards,

Josef

[kguntur]

What kind of mesh continua are you using?

[jcamilleri]

Hi kris,

I am using the surface remesher and trimmer models. People seem to have done it with these models (see http://www.cd-adapco.com/thesis/use-...s-impact-phase)

Regards,

Josef

[kguntur]

Did you have the edge of the circle marked as feature? If not that might be helpful.
If you already did that, you could try giving a custom mesh condition to the feature edge and see if that helps.

[me3840]

Can you post images of the CAD and the mesh?

[jcamilleri]

Hi me3840

Please fine the images attached with this post.

Regards,

Josef

[me3840]

What do the initial and remeshed surfaces look like?

[jcamilleri]

Hi kris me3840,

Kris I did try your suggestions but with not luck

me3840 I did attach two images with the previous post. The first image shows tha CAD model and the six pink circles show the imprinted sketches of the pressure transducers on the wedge bottom. The second image shows the meshed domain with the triangles on the wedge bottom the pressure transducers (circles became triangles).

any ideas?

[me3840]

Yes, I saw those images, but I'd like to see what the initial and remeshed surface look like to find out where the problem is.

[jcamilleri]

Hi me3840,

Attached please find the requested images. What I did was just change the representation from volume mesh to initial surface and remeshed surface. I am understanding you correctly right?

Regards,

Josef

[me3840]

Yes, you understood me correctly, but I do not see the circles in the images you posted.

[jcamilleri]

Hi me3480,

Attached please find the images.

Regards,

Josef

[me3840]

The remeshed surface doesn't appear to have the circles, so the problem lies there. What are the settings you used for curvature?

[jcamilleri]

Hi me3840,

I tried 36, 72 and 144 #pts/circle with no luck. I think that with 144 points on a 9mm circle it should be able to create it no? I also enabled curvature deviation distance and set it to 1mm and 0.1mm and still. When I created a new geometry part from the cad model, I set the tessellation density to fine and mark feature endges to All CAD edges so that the transducers become feature edges as suggested by kris in a previous comment in this thread. Can I send you the model, in that way you can have a better look?

Regards,

Josef

[me3840]

Sure, this is probably small enough that I could look at it quickly.

[jcamilleri]

Can you give me your email address please?

Regards,

Josef

[me3840]

Your holes are really, really small, smaller than your specified mesh sizes. If you reduce the target size on the surface of the hole to 1% of your base, the circle gets resolved. See here.

http://imgur.com/iNM0rEp

[jcamilleri]

Hi me3840,

Thank you for taking your time to look at my problem. I was refining the mesh but not enough! Now it worked Thanks again for your help.

Regards,

Josef