Learning Forum

[ystein]

Hi All, 

I am essentially trying to deform a square into a rhombic shape to study it's shearing properties as this picture: 

 

My created geometry is below, where I would be pulling the four rounded corners of the square to deform . I would then want the walls to slide at different slopes to stretch into the rhombic shape. The walls have to be straight lines, but the logic is that all I am doing is changing the slope of the walls given the positions of the corners. 

 

Therefore, I have chosen CG_MOTION to define the motion of corners and DEFINE_GEOM to define the motion of the wall.

Unfortunately, when I hook in deforming zones for the walls, I cannot display ZONE MOTION of the corners! Nothing shows up in the display. When I preview mesh motion, my geometry doesn't exist anymore. It displays as such: 

 

It is the skeleton of my geometry used to create the mesh zones. I don't know what's happening! 

This is what it says in the TUI: 

Dynamic Mesh Statistics:

Minimum Volume = 5.92234e-02

Maximum Volume = 3.64152e+00

Maximum Cell Skew = 5.01364e-01 (cell zone 3)

Minimum Orthogonal Quality = 0.00000e+00 (cell zone 3)

Warning: minimum orthogonal quality less than 0.05.

 

Warning: left handed faces detected!

 

This is my UDF code: 

CGMOTION: 

define geom: I use a slight variation of this for every wall but the backbone is the same. 

 

Any help is appreciated. I should also note that "display mesh" is checked in mesh motion. After I run the preview, If i go back to mesh display, I cannot recover my original mesh.  

 

I can also provide other screenshots of my dynamic mesh zones if needed! Thank you. 

[ystein]

ok so update: 

I now added the interior body to also be deforming, but this is my result before negative cell volume is detected. 

 

Any suggestions to improve mesh? / reasons for why the walls aren't changing slopes?