Hi M Usman,
Thank you for sharing the designs. Now if you observe both the geometries are structurally quite different and structurally is not topologically but as per the structural function.
I'll refer to the violet geometry as Model A and the gray one as Model B just to avoid any confusion. So if observed in Model A, there are no columns or the transverse members as observed in Model B. These members will definitely add extra stiffness to the geometry.
I'll be happy to assist you with further queries but, if noticed the two comparison bodies are structurally different in the critical aspects, so they're bound to provide different results.
Thus it would be a good practice to get the results for the manufacturing design rather than the conceptual design, the design can be further optimized on various parameters to use the FEA to get a better and more efficient design.
You can use the approach of beams or slender bodies as observed in the geometry as per the requirement to get a better and more efficient FEA model for Model B.
Hope this helps!
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