How does the Non-Design growth influence and impact the Design?

The Non-Design growth can be activated, thus all Non-Design Spaces grow a little bit beyond their boundaries to ensure a trouble-free and clean intersection. This is done with an automatic detection of Non-Design faces. With the Advanced User Settings the automatic Non-Design growth can be activated.

If Interfaces or boundary conditions are applied, the Non-Design growth doesn’t need to be activated. The Interface surface already ensures a trouble-free intersection to create all the needed functional surfaces.

These two options create different transitions between the Non-Design Spaces and the overall Design structure.

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The disabled Non-Design growth (default) creates an undercut and therefore a smooth transition between the Non-Design Space and design structure. Nevertheless, in this area stress risings can appear. The Post Processing with a machining process like milling is much easier because no unintentional cuts into the design structure can happen.

The enabled Non-Design growth creates a hard transition with a notch to the design structure. This transition leads to stress risings at the notch which influences the fatigue life of the part. Furthermore, the Post Processing after the manufacturing of the part with e.g. milling is quite difficult. The position of the notch should not be moved any further in the Design direction.

It is not quite clear which transition has a better impact on the fatigue life of a part and has to be evaluated by the engineer for each case separately.

Activate the Automatic Non-Design Growth: