Keeping G2 continuity through CFD-driven edits

And in NX 2212 feeding STAR-CCM+ 2402, a 0.5 mm fillet tweak on an underbody diffuser keeps breaking G2 curvature and spawning sliver faces, stretching the loop from about 9 to 24 minutes per variant. What surfacing or heal settings (tolerances, face-merge, mesh prep) are you using to keep a watertight A-surface and stable aero iterations without dulling the curvature?

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NX Heal Geometry “Merge Faces” angle 0.3° + min face 0.2 mm fixed “sliver faces” without dulling G2. You tried?

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