I am modeling a circular plate of 1 mm diameter and thickness of 0.1 mm and when I do the meshing, the ANSYS closes automatically, so I want to know: does the thickness create any problem in meshing or is there any limit for thickness to be considered when meshing in ANSYS?
The thickness can give you problems in any finite element program. If the length to thickness ratio is to large the elements are stiffer do to locking effects. You can avoid/reduce this effectif you use quadratic solid elements or shell elements. Another point is, if your thickness to element length ratio is very large you get problems with the condition of your matrix. In your case you have only to think about locking.
Ratio of radius to thickness of the plate is small - is only 10. Therefore unlikely the thickness is a reason of critical situation when the mesh is generated. One can assume that when you set small step partition conflict arises between the desired and ordered memory.
It seems that you have a problem related to meshing which has nothing to do with the stiffness locking issues indicated above (that will only occur during stiffness matrix computation and solution computation). Ratio os thickness is indeed small, moreover, ansys hexa elements are full of numerical remedies to avoid any form of locking (obviously within certain limits)...so I think that you will not experinece any problem during solution computation. The fact that ansys crashes during meshing is probably a problem with something related to mesh computation. try to mesh the same geometry but with a sacel factor applied (use a disc with 10mm of diameter and 1 mm thickness). If that succeds then try to apply a scale down of 10% to get the mesh for the original size. Just an idea!
Thank you Moreira sir. Your suggestion is really a key solution to my solve problem and i will the try for the scale factor to avoid the problems during meshing.
Sir, I was advised to use quad or beam element for analysis. Since i am new to ANSYS I can't figure out the difference between the element types and its uses. I kindly request you to help me by informing the uses of SHELL elements. The stress distribution across the thickness of 0.1mm (circular plate) is only the reinforcement which is covered by a matrix. So if a load is applied it distributes from matrix to reinforcements and not directly to 0.1mm thickness circular plate.
Thank you Samir Lemes. Your information about the Shell element really helped me a lot. But you have mentioned that while going for solid finite elements, it should be ensured that H*L*D of the element is should be near to 1. How does this is related to circular object which as only radius and thickness?
If you are asking a theoretical question: Thickness matters if you are modeling plane stress problem, if you are modeling plane strain problem, you dont care for thickness.
I modeling Plane stress problem but my modeling is about nano reinforcement which i am considering as a 3D solid element and while i try to solve it in ANSYS i get error related to memory problem and i can't model for the full volume of my geometry.
How is it that your model is a circular "solid" of 1mm diameter and you want to include nano-reinforcement in this model? That doesn't fit. If you are talking about an RVE, the circular plate should be scaled further down. Besides, if you are talking plane stress, why do you even use 3D Solid! in the first place? Your geometry should have no Volume but rather PLANE! solid elements. With some caution you can still use 3D-1D elements (such as beams or linkbars) to model nanofibers.
Generally ansys quits or suffers memory problems if there is a loophole in some of its procedures (such as meshing). Probably your mesh parameters is problematic, like size control, overlapping areas, repeated meshing..and such.
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