forked from 1b-agent/fieldcraft-upstream
jyvikoandClaude Opus 5.5
6d9452ad84
The oracle binary (modelcraft-testkit) runs each case's recipe through the command engine, measures its quantities by JSON pointers into step outputs or commands, compares them with the cited references and the frozen fixtures, and writes docs/oracle.md. 20 theory cases (patch tests of every solid element, Timoshenko cantilevers, Lame, Kirsch, beam frequencies, torsion and bending through couplings, explicit waves and impact, CDT invariants), 8 published benchmarks (MacNeal-Harder patch, straight and curved cantilevers, thick cylinder, Scordelis-Lo with solids, NAFEMS LE1, LE10, FV32) and 10 pending cases with citations. Co-Authored-By: Claude Opus 5.5 <[email protected]> Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
9 lines
553 B
Markdown
9 lines
553 B
Markdown
# Constant-stress patch test, hex8
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A unit cube of eight hex8 cells whose shared points are moved off the regular grid (every
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face, edge and centre point; the corners stay), so every element is distorted (one mesh.block per cell). Symmetry on the
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faces x = 0, y = 0 and z = 0; tractions 1, 2 and 3 on the faces x = 1, y = 1 and z = 1
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(E = 1000, ν = 0.25). The exact solution is the uniform stress diag(1, 2, 3) with strains
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ε_i = (σ_i − ν(σ_j + σ_k))/E, which every conforming element of a convergent formulation
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reproduces exactly on any mesh.
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