Dear Lady/Sir,

I have one other thing that kept me wondering while working with Hypersizer. I am using the Angle-grid Concept of the Grid-Stiffened Panels family to optimize the structure for the loads I have derived. I am also using the analytic model developed by me for comparison. The approaches to most of the failure modes/stiffness calculations, etc. used in my software is to a large extent different from what is used in Hypersizer. One thing that I recently found not matching in the 2 approaches is actually related to geometry. I will try to explain it with the help of the two pictures attached below.

The first picture is a sketch made in CATIA to help me explain my point. The green lines indicate that the sketch is fully fully constrained and therefore it is the only geometrical solution available for the dimensions shown. I have drawn 2 cells of 3 different Angle grid panels with Angles of 60°, 45° and 30°. The Axial stiffened spacing used is 50mm. The way I understand "spacing" is as the distance between 2 adjacent parallel webs. And from my CATIA sketch one can recognize that the angle web spacing for the 3 cases is: 50, 70.711, 86.603 (all dimensions in mm). And the length of the web segment in between two adjacent angle webs (crippling/Euler buckling length) is 57.735, 70.711 and 100 mm respectively. The dimensions in brackets are the so-called reference dimensions.

When I look at the way Hypersizer is visualizing the same values I can see that the abovementioned spacing is 57.74, 70.71 and 100 mm. This actually means that Hypersizer shows the value of the web segment length instead of taking the distance between two parallel webs as the web spacing.

I am trying to match the results from Hypersizer with my theoretical approach and, since my stiffness and local buckling formulation is spacing-based, I need to know if this is just a visualization mistake or if it runs deeper. I suppose it is just in the way it is visualized in the sizing form and it is not related to any computations.

Thanks a lot for your help and for letting me use your great software!

Kind regards,

Leonid