SimScale CAE Forum

Problem - thin plate analysis


#1

Hello, I am new to Simscale. I pooglądałem all the materials and I thought that I already know how to use the program.
I have worked with many programs and more I understand the method.
I did a simple example - loaded pressure plate on the surface. I did a lot of tests and different settings but still gets some strange results.
I suspect that the more I was wrong :slight_smile: - please help.
The results should be smoother and should not have any peaks - this is my opinion.
https://www.simscale.com/projects/gkondracki/plate_2/ - Here it looks better
https://www.simscale.com/projects/gkondracki/plate_1/ - It looks very strange.


#2

Hello @gkondracki,
the results that you are getting are a result of the coarse mesh (on element through thickness) in combination with the first order elements (constant stress per element) that you are using.

A second order mesh should result in a better stress distribution. To get accurate results you would however need at least two second order elements through the thickness of your plate.

Best,
Richard


#3

Adding to what @rszoeke said, use the Tetrahedral parametric with Minimal mesh edge length [m] and Maximum mesh edge length [m] of 0.003 since thickness of your plate is 0.006. This will make at least two elements over the thickness. Please note that this will create a bigger mesh in case of second order. Therefore you may need probably 8 cores for mesh and simulation.

I hope this helps. If you have any question/s, feel free to ask.

Best,
Ahmed.


#4

For me it makes the mesh of 309075 nodes using minimal and maximum mesh edge length of 0.003, second order with moderate refinement. This will be doable using 8 cores for simulation. You can try and let us know if you are now getting the desired results :wink:

Best,
Ahmed


#5

Thank you very much for help.
I did as suggested and actually results look very good.
I’m from the old school - once a lot of elements that was a big problem :slight_smile:
Now it went quickly and smoothly.
Thanks again for your help.
Best
Greg (Grzegorz)


#6

Hey Greg!

Glad that now results look good! :slight_smile: If you want to know why second order mesh is better in most of the cases, please have a look at this forum post: When should I use a second order mesh?

Best,
Ahmed


#7

Hi Ahmed!
I thank you very much for your help and explain the types of elements. I’d rather be using a second order - I used to be problems with the first - big mistakes and client denied the results.


#8

Hey Greg!

Glad to help you! :slight_smile: I hope that your client will be satisfied now with second order mesh results :wink:

Best,
Ahmed