The area of a constrained plane section
 

I need to determine the area magnitude of two plane sections. I have generated a report for the area magnitude of these two constrained plane sections. STAR CCM gives the area magnitude of one of them. For the other, it shows zero.
What to do to get the area magnitude of other one?

Which report type did you use? For example, with "frontal area" report the problem could be setting the right "view up" and "normal" properties.

You could create a field function with a constant value 1 and do a surface integral for the constrained plane for this field function