From 5050b9e71e14a38a2cdf84a8f9c498dfb6f0b660 Mon Sep 17 00:00:00 2001 From: Dane Sabo Date: Tue, 21 Apr 2026 21:40:04 -0400 Subject: [PATCH] =?UTF-8?q?fat-entry=20scram:=20n=20decays=200.047?= =?UTF-8?q?=E2=86=920.009=20over=2060s=20from=20fat=20X=5Fentry?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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) --- code/scripts/reach/reach_scram_pj_fat.jl | 1 + .../2026-04-21-polytopic-sos-tikhonov.tex | 31 ++++++++++++++++--- 2 files changed, 28 insertions(+), 4 deletions(-) diff --git a/code/scripts/reach/reach_scram_pj_fat.jl b/code/scripts/reach/reach_scram_pj_fat.jl index c790d84..ff12ade 100644 --- a/code/scripts/reach/reach_scram_pj_fat.jl +++ b/code/scripts/reach/reach_scram_pj_fat.jl @@ -18,6 +18,7 @@ using Pkg Pkg.activate(joinpath(@__DIR__, "..", "..")) using LinearAlgebra +using Printf using ReachabilityAnalysis, LazySets using JSON using MAT diff --git a/journal/entries/2026-04-21-polytopic-sos-tikhonov.tex b/journal/entries/2026-04-21-polytopic-sos-tikhonov.tex index e51f41b..864aab0 100644 --- a/journal/entries/2026-04-21-polytopic-sos-tikhonov.tex +++ b/journal/entries/2026-04-21-polytopic-sos-tikhonov.tex @@ -181,10 +181,33 @@ One-session task. \subsection*{Other odds and ends} -\apass{Scram entry-set expansion (user's morning point 2) queued; not -done this session. The LOCA-driven scenario is a separate reach run -that needs to complete first, then its final-state bounding box feeds -into the scram \textit{X\_entry}.} +\textbf{Scram entry-set expansion (user's morning point 2) --- +landed later this session.} Built +\texttt{code/scripts/reach/reach\_loca\_operation.jl} (LQR reach under +$Q_{\mathrm{sg}} \in [0,\ 1.5 P_0]$, the steam-line-break envelope, +for 3~\unit{\second} horizon) and +\texttt{code/scripts/reach/reach\_scram\_pj\_fat.jl} (bounding-box +union of hot-standby + heatup-tight envelope + operation-LQR envelope ++ LOCA envelope, clamps LOCA's numerical outliers on precursors to +physically plausible bounds, reruns PJ scram reach). + +Result: $n$ decays monotonically +\textbf{$0.047 \to 0.021 \to 0.0094$ over $\{10, 30, 60\}$~\unit{\second}}, +factor-of-five per minute even starting from the fat entry (which +includes the LOCA-perturbed post-operation state). Temperatures +fall from $[226,\ 361]\,^\circ\mathrm{C}$ (clamp-saturated initially) +toward the decay-heat equilibrium. No step-budget truncation; +23{,}919 reach-sets over 60~\unit{\second}. $X_{\mathrm{exit}}$ +threshold of $n \leq 10^{-4}$ still not reached in 60~\unit{\second}; +same $T_{\max}$-vs-plant-decay mismatch flagged in the earlier scram +entry. \emph{But}: this is now a defensible obligation because the +entry set represents ``anywhere the plant could realistically be,'' +not the narrow 1~K box around $x_{\mathrm{op}}$ of the earlier run. + +\apass{The LOCA reach itself is numerically loose (box-hull propagation +amplifies slow precursor modes under large disturbance, so horizons +$> 3$~\unit{\second} blow up). A proper zonotope-generator +propagator would fix this; deferred.} \apass{Heatup with steam-dump $Q_{\mathrm{sg}}$ demand (user's point 3) queued; a one-line change to \texttt{main\_mode\_sweep.jl}'s