Scram PJ reach from the bounding-box union of:
- hot-standby box (mode_boundaries.q_shutdown)
- heatup-tight reach envelope (results/reach_heatup_pj_tight.mat)
- operation-LQR reach envelope (results/reach_operation_result.mat)
- LOCA operation envelope (results/reach_loca_operation.mat, 3s)
with precursor + temperature outliers clamped to physical bounds.
Results at probe horizons:
T=10s: 10890 sets in 480s wall — n ∈ [-8e-4, 0.047] T_c [231, 362]
T=30s: 16925 sets in 2892s wall — n ∈ [-4e-4, 0.021] T_c [229, 361]
T=60s: 23919 sets in 705s wall — n ∈ [-2e-4, 0.009] T_c [226, 359]
Monotone n decay, factor-of-5-per-minute even from the wide union.
This is the defensible scram-obligation version: starts from anywhere
the plant could plausibly be (including LOCA-perturbed operation
state), proves n decays. X_exit(scram)=n≤1e-4 still not reached in
60s — same T_max-vs-plant-decay mismatch previously flagged.
Fixed: missing Printf import that had failed the summary block on the
first run (results still computed correctly, just the final print
errored; the matwrite is after the print so the mat file wasn't
saved on that run).
Journal entry for 2026-04-21 extended with the fat-entry result +
the LOCA-reach 3s-horizon numerical-looseness apass. 38 pages.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Morning-review items 2 and 3.
Point 2 (scram X_entry expansion):
- reach_loca_operation.jl: LQR reach under Q_sg widened to
[0, 1.5*P_0] (steam-line break envelope) for 3 s horizon.
Longer horizons cause numerical blowup in the box-hull
reach propagator due to slow precursor modes amplifying
under large disturbance — documented in the script.
- reach_scram_pj_fat.jl: computes bounding-box union of
hot-standby + heatup-tight + operation + LOCA reach
envelopes, clamps obvious numerical outliers on precursors
and temperatures, builds a fat X_entry(scram), runs scram
PJ reach. Result pending (TMJets compiling).
Point 3 (heatup steam-dump Q_sg):
- configs/heatup/with_steam_dump.toml: Q_sg ∈ [0, 0.05·P_0]
as bounded parameter.
- reach_heatup_pj_sd.jl: 12-state RHS with x[10]=Q_sg (dx=0,
augmented bounded param) and x[11]=t. Running in
background.
Tight-entry heatup via the new TOML-config reach_heatup_pj.jl
reproduces the previous all-6-halfspaces-discharged result
(300s horizon, T_c envelope [281.05, 291.0]). Refactor
preserves semantics.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
