Zero, small, or negative element area?

[louisa]

Hello Everyone,

I received the following error message while running the simulation.

"Error in job try: The area of 505 elements is zero, small, or negative. Check coordinates or node numbering, or modify the mesh seed. The elements have been identified in element set ErrElemAreaSmallNegZero."

The mesh is still very very coarse (seedEdgeByNumber, 2 or 4) and the sizes of the elements are quite uniform. Therefore the above message seems very wired to me. I cannot identify what is the problem with the elements. I appreciate it if you can give me some clue. Thanks!

 

[xerf]

Open the .odb file. (ABAQUS should have created one despite the error message).
Go to Visualization->Tools Menu-> Display Group->Create
Item : Elements

You should find an element set named "ErrElemAreaSmallNegZero".

 

[louisa]

Thank you so much, xerf. Now I found this region of small or negative element area.

But still I cannot identify the problem. This area of the elements in this region is the same as other regions.

I googled "ErrElemAreaSmallNegZero". It seemed that this is a problem common to 2D simulation. Some people suggested that maybe the normal to the elements on the surface is pointed to z- direction, and it should be reversed to z+ direction. But I don't know how to check on the normal of the problematic faces and how to reverse the face normal.

 

[louisa]

I know that the normal can be flipped in the property module. But I want to avoid negative normal from the very beginning. Since the simulation runs for many iterations, it is impossible to find the problematic faces and then reverse the normal manually every time. How to define the faces with positive normal?

 

[Bat585]

Hello

I don't now if you have meshed your part with abaqus pre proc or by yourself, but I had the same problem with a mesh I had generated by myself and I solved it by changing the order of the nodes on each element

Hope I helped

bat585

 

[corus]

Sometimes if you use contact and adjust overlapping nodes then the mesh can change from what you originally thought it was. Viewer will show you the mesh that has been used after nodes have been adjusted.

corus