what is the relationship between material angle in integration point and AOPT in material card

Altair Forum User

Hello, everyone. Recently I am very confused by the material angle defined by B1, B2, B3 in *section_shell and by AOPT  in material model card. For example, in my research case, there are three through thickness integration points that represent three different fiber tows (t1, t2, t3). The three fiber tows have different constituents  equations and different material angles (+60/0/-60). A right represent is shown in figure 1 (a). Then I defined their AOPT respectively shown in Figure 2.

 

Figure 1

 

Figure 2

Then if I also make icomp=1 and give 60/0/-60for B1, B2 and B3 as shown in Figure 3, then what's the relation between figure 2 and figure 3. I don't know if this is right? I am worried about whether the material angle is right. Because it will influence the results a lot.

Figure 3

 

Thank you for your patience. We can discuss here. I am eagle to hear your advice.

 

Thanks.

Altair Forum User

Hey, guys. I find this document very helpful for this question. I attached it here. 

 

Thank you.

 

 

Unable to find an attachment - read this blog

Altair Forum User

This document well answered how the mat coordinate system defined and how the mat coordinate system rotates.