Hello guys,
I'm currently trying to simulate a 3 point bending test to get the best material arrangement for high bending stiffness in a composite monocoque, while keeping the weight low.
The laminate i strive for is a sandwich structure with an aramide honeycomb core in the centre and three plies of different material on top and on the bottom.
These are the steps I did so far:
1) I created a CAD model, imported it to HyperMesh, organized the componets (specimen, impactor, support) and meshed them with 2D elements.
2) I created the materials. MAT1 for the impactor and the support of the 3 point bending test, MAT8 for the different plies and MAT9ORT for the honeycomb core.
3) After that I created the properties. PSHELL with an elementthickness of 2 for the impactor and support, PCOMPP for the plies and PSOLID with the honeycomb material for the core.
4) Then I created the different plies. 6 with the MAT8 material for the top and bottom layers and 5 with the MAT9ORT material for the core to get a total of 5 elements over the thickness of the core. The material type for all plies is ORTHOTROPIC.
5.1) I created a laminate with the 5 core plies and then did a 'shell to solid conversion' with this laminate. After that I got a new component with 5 elements over the thickness.
[5.2) In a second try I did the 'shell to solid conversion' with the plies of the core which led to the same result as 5.1]
6) I assigned the PCOMPP property to the specimen elements, otherwise the laminate and layers weren't visible over 2D detailed element representation.
7) I updated the laminate with the other 6 plies.
8) Finally I created the load collectors and the load step, an output request for CSTRAIN and CSTRESS
9) I started OptiStruct to run the analysis.
But after a few seconds i got these errors:
*** ERROR 14: Missing MAT # 5 referenced by PLY # 7,
(existing MAT with this ID is of incorrect type).
*** ERROR 14: Missing MAT # 5 referenced by PLY # 8,
(existing MAT with this ID is of incorrect type).
*** ERROR 14: Missing MAT # 5 referenced by PLY # 9,
(existing MAT with this ID is of incorrect type).
*** ERROR 14: Missing MAT # 5 referenced by PLY # 10,
(existing MAT with this ID is of incorrect type).
*** ERROR 14: Missing MAT # 5 referenced by PLY # 11,
(existing MAT with this ID is of incorrect type).
*** Errors with missing, incorrect or duplicate IDs found 5 times.
So when I got back to the model to check the properties, I wasn't sure if the PSOLID property and the MAT9ORT material are assigned to the plies in the laminate or to the new created component for the solids of the conversion.
I want to get a laminate with from top to bottom: 3 layers of PCOMPP MAT8, the PSOLID MAT9ORT core and then 3 layers of PCOMPP MAT8 again. Is it even possible to creat such a laminate and if yes, in wich order should I assign the properties and creat the laminate?
Or are there other ways to simulate this kind of sandwich structure in HyperMesh and OptiStruct?
Here I uploaded the HM file so you can have a detailed look at my model:
These are some screenshots of the different views on the model:
I hope you get my problem and can help me fix it.
Thanks in advance!
