Engineering software should show its work.
What has been checked, how, with what result — and what has not been checked. Every number below is reproducible in the tools themselves; the regression assertions ship with the site.
Independent-solver comparison and synthetic recovery
| Test | Truth | Result | Status |
|---|---|---|---|
| Synthetic blockage, 50 % area, 20 m long, 0.2 m sensor noise | face at 390 m from valve | 390.5 m · 50.3 % area remaining · 20.0 m extent | pass |
| Synthetic leak | 700 m from valve | 700.1 m · leak flow within 8 % | pass |
| Clean pipe | no reflector | no echo with |r| ≥ 0.05 | pass |
| Spurious 400 m transient late in the record | closure at 0.005 s | closure found at 0.0045 s; transient reported as an echo, not as closure | pass |
| Independent solver (TSNet, WNTR-based): leak | 300 m from valve | 307 ± 9 m · 4.3 L/s vs 4.9 L/s | pass |
| Same trace: additional echoes | none physical | two additional strong echoes (~562 m, ~877 m) from the other solver's boundary treatment are reported, not suppressed | documented |
| Sensitivity sweep, closure 10 ms, noise 0.1–0.8 m, 500–2000 Hz | blockage at 390 m | 5 / 5 detections in every case, 0 false alarms | pass |
| Sensitivity sweep, closure 50 ms / 200 ms | blockage at 390 m | 4 / 5 and 1 / 5 detections — slow closure degrades detection | documented |
Not yet validated: against published field hammer-test data with ground truth; leak sizing on real lines; branched networks, column separation, viscoelastic pipe walls. The tool's Method panel lists every modelling assumption.
Convergence diagnostics and known-truth recovery
| Case | Result | Status |
|---|---|---|
| Seismic benchmark, 3 chains × 3000 | all impedances inside 95 % CrI · max R̂ 1.006 · min ESS ≈ 440 | pass |
| Pipeline blockage, synthetic | a, f, x, blocked area inside 95 % CrI · R̂ 1.09 | pass |
| Pipeline leak, synthetic | x = 700 ± 4 m (true 700) · orifice 0.0050 (true 0.0050) · R̂ ≤ 1.09 | pass |
| Well-log petrophysical, 7-zone synthetic log | 13 / 14 truths inside CrI · rms residual 1.0 σ | pass |
| Well-log petrophysical, sample_well.csv with default endpoints | REVIEW REQUIRED · R̂ 1.02 · residual 2.3 σ — the default matrix endpoints do not match that log; the residual tracks show it | documented |
| Independent TSNet trace, full-waveform fit | NOT CONVERGED (R̂ ≫ 1): the solver cannot represent the other code's boundary artefacts; the diagnostics say so rather than reporting a confident wrong answer | documented |
Status CONVERGED requires split-R̂ < 1.01 and bulk and tail ESS > 400 on every parameter; every run is reproducible from its seed and reopens exactly from the saved record.
Provenance and scope
Johancsik soft-string drag (JPT 1984) with build-rate curvature; effective submerged weight separating steel, internal and annular fluid; Mitchell post-helical contact; Dawson-Paslay, Chen-Lin-Cheatham and Lubinski buckling limits. Sign convention and lockup definition are stated on the page: required push is a positive magnitude, helical onset is reported separately from lockup, and lockup is the first depth at which required push reaches injector capacity or helical drag runs away. Not validated against commercial torque-and-drag software or field lockup records; pressure-area effects are not implemented. It is a screening tool and is labelled as one.