Antoine
b88657b00c
Sources: 3 KBS capture sessions (20260210-132817, 20260210-161401, 20260210-163801)
Key changes:
- Mass corrected: 974 kg (p173) → 11.33 kg (p1) — KBS ground truth
- Beam length confirmed: 5,000 mm cantilever
- BCs confirmed: left fixed, right 10,000 kgf downward
- Material confirmed: AISI Steel 1005, density 7.3 g/cm³
- Mesh confirmed: CQUAD4 thin shell, 33.7 mm elements
- Hole geometry: span 4,000 mm (p6), offsets 500 mm fixed
- 3 gaps closed (G1, G2, G8), 6 new gaps identified (G10-G15)
- New expressions: beam_half_height, beam_half_width, beam_length, p6
Files: CONTEXT.md, kb/_index.md, kb/_history.md, kb/components/sandwich-beam.md,
kb/materials/steel-aisi.md, kb/fea/models/sol101-static.md, kb/dev/gen-002.md
85 lines
3.8 KiB
Markdown
85 lines
3.8 KiB
Markdown
# CONTEXT.md — Hydrotech Beam Structural Optimization
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## Client
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Hydrotech (internal test fixture)
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## Objective
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Minimize beam mass while meeting displacement and stress constraints. Single-objective: minimize mass, constrain displacement (≤ 10 mm) and stress (≤ 130 MPa).
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## Key Parameters — Confirmed (Gen 002)
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| Parameter | NX Expression | Current | Range | Units | DV? | Notes |
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|-----------|--------------|---------|-------|-------|-----|-------|
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| beam_half_core_thickness | `beam_half_core_thickness` | 20 | 10–40 | mm | Yes (DV1) | Core half-thickness |
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| beam_face_thickness | `beam_face_thickness` | 20 | 10–40 | mm | Yes (DV2) | Face sheet thickness |
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| holes_diameter | ❓ (Gap G14) | 300 | 150–450 | mm | Yes (DV3) | Lightening hole diameter |
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| hole_count | `hole_count` | 10 | 5–15 | integer | Yes (DV4) | Number of lightening holes |
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| beam_length | `beam_length` | 5,000 | Fixed | mm | No | ✅ Confirmed KBS |
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| beam_half_height | `beam_half_height` | ❓ (Gap G12) | — | mm | No | Half I-beam height |
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| beam_half_width | `beam_half_width` | ❓ (Gap G13) | — | mm | No | Half flange width |
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| hole_span | `p6` | 4,000 | TBD | mm | Potential (G15) | Total span for hole distribution |
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## Constraints
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- Max tip displacement: ≤ 10 mm
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- Max von Mises stress: ≤ ~130 MPa (steel, conservative — Gap G9)
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- Mass tracked via NX expression **`p1`** ← CORRECTED from `p173` (Gen 002)
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## Baseline Performance — Confirmed (Gen 002)
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| Metric | Value | Source | Confidence |
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|--------|-------|--------|------------|
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| Mass | **11.33 kg** | NX expression `p1`, KBS session | ✅ High |
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| Tip displacement | ❓ **NEEDS RE-VERIFICATION** (Gap G10) | Was 22 mm at old model state | ⚠️ Low |
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| Max stress | ❓ **NEVER MEASURED** (Gap G11) | — | ❌ None |
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| Material | **AISI Steel 1005** | KBS session | ✅ High |
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| Density | **7.3 g/cm³** | KBS session | ✅ High |
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> ⚠️ **Mass discrepancy resolved:** Intake reported ~974 kg (`p173`). KBS session confirmed 11.33 kg (`p1`). See `kb/dev/gen-002.md` for full analysis.
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## Boundary Conditions — Confirmed (Gen 002)
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| BC | Location | Value | Source |
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|----|----------|-------|--------|
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| Fixed support | Left side (full edge) | All DOF constrained | ✅ KBS session |
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| Applied force | Right side (free end) | 10,000 kgf downward (−Y) | ✅ KBS session — "project requirement" |
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| Configuration | Cantilever | Left fixed, right loaded | ✅ KBS session |
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## Mesh — Confirmed (Gen 002)
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| Property | Value | Source |
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|----------|-------|--------|
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| Element type | CQUAD4 (thin shell) | ✅ KBS session |
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| Element size | 33.7 mm (67.4/2) | ✅ KBS session |
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| Idealization | Promote body → mid-surface extraction | ✅ KBS session |
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## Hole Geometry — Confirmed (Gen 002)
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| Property | Value | Notes |
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|----------|-------|-------|
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| Span | 4,000 mm (expression `p6`) | Total distribution length |
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| Start offset | 500 mm from beam start | Fixed requirement — not parametric |
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| End offset | 500 mm from beam end | Fixed requirement — not parametric |
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| Collision check | Required at DV extremes | 15 × 450 mm in 4,000 mm → overlap |
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## Model Files
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- NX Part: `Beam.prt`
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- FEM: `Beam_fem1.fem`
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- Idealized part: `Beam_fem1_i.prt`
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- Simulation: `Beam_sim1.sim`
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- Solver: NX Nastran SOL 101 (static structural)
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## Future Expansion
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- Material alternatives: Aluminum 6061, Stainless Steel ANSI 310 (per Antoine, KBS session)
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- `p6` (hole span) as additional design variable (pending decision)
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- Mesh refinement (Antoine: "Eventually we're going to be able to refine the element size")
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## Decisions
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- 2026-02-08: Project received from Antoine
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- 2026-02-10: KBS sessions processed → Gen 002 KB update. Mass corrected, BCs confirmed.
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## Status
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Phase: Pre-optimization (baseline re-verification needed)
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Generation: 002
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Channel: #project-hydrotech-beam
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Last KBS session: 2026-02-10T16:38:01
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