Do cheap beam and 2D models rank candidate cantilever designs like 3D finite elements?
research/simdesign-rank
Do cheap beam and 2D models rank cantilever designs like 3D finite elements? Yes on 3 seeds of 80 designs: Kendall τ 0.987–0.996 and the 3D-best design always ranked first, even though single-design merit is off by up to 14%; stubby sections agree least; stylised, one load case.
What it found
Stylised. 80 random cantilever designs per seed (3 seeds) are ranked by stiffness per mass with Euler–Bernoulli and Timoshenko beam theory and 2D plane-stress FE, and compared with a 3D finite-element reference (scikit-fem). Single-design merit is off by up to 14% (Euler–Bernoulli, stubby sections), yet every cheap model ranks the designs almost identically: Kendall τ 0.987–0.996 with 3D, 3D’s best design always ranked first, top-8 overlap 7 or 8 of 8. Stubby designs agree least (τ 0.96–0.99). Limits: one load case, assumed material, a coarse 3D reference, no stress or constraints in the ranking.
A figure from its own output
Paper, code and results
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Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.