Does the peak stress at the fillet tangent point of the L-bracket converge under graded mesh refinement?
research/simdesign-gradedtip
Does the L-bracket's peak stress at the fillet tangent point converge under graded mesh refinement? Yes for four designs: it flattens at 1.09–1.14× its 1.5 mm value (0.0–1.1% change over the last 4× refinement down to 0.025 mm), so the 2 mm region's mesh dependence is a resolution effect; the 16/15/2 design is marginally over 100 MPa when converged; stylised 2D, no reference solution.
What it found
Preliminary, stylised 2D plane stress. Uniform meshes left the element-centroid peak stress of the 2 mm laser-cut bracket still rising. Refining only around the fillet tangent point, down to 0.025 mm elements, the peak of four designs flattens at 1.09–1.14× its 1.5 mm value (0.0–1.1% change over the last 4× refinement), so it has a finite limit and the earlier mesh dependence was a resolution effect. The converged plateau shifts about 2% with the grading rate; the 16/15/2 design sits marginally above the 100 MPa limit (101.9 MPa). No independent reference solution was compared; nothing was optimised.
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.