Abstract:
This paper investigates the challenges of using complex solid models from design software, such as Pro/Engineer, for downstream engineering applications, particularly Finite Element analysis, which often fail due to excessive detail or geometric inaccuracies referred to as "dirty geometry". The research identifies several sources of these problems, including numerical imprecision, degenerate surfaces (e.g., tori with zero major radius), unnecessary topology like seams on cylindrical faces, overly complex details such as small fillets, and positioning errors in assemblies. To address these issues, the project explored multiple simplification strategies, primarily focusing on feature suppression within the native CAD environment and direct boundary representation editing using external geometry engines like ACIS. A prototype software system was developed to automatically detect problematic geometry, such as degenerate surfaces and small features, and to semi-automatically guide users through the simplification process by managing complex parent/child feature relationships. The results demonstrated that these tools significantly improved the success rate of preparing complex production models for meshing with applications like CUBIT, transforming a previously unreliable process into one approaching production-worthiness by enabling the diagnosis and removal of show-stopping errors that would otherwise prevent successful Finite Element analysis.
