Published May 13, 2026 | Version 1.1.1
Software Open

Integrity Code Series - Week 9 - CUI Coupled Thermohygro-Electrochemical Simulation

Authors/Creators

  • 1. Independent Researcher

Description

Three-way coupled physics-first simulator for Corrosion Under Insulation (CUI) on insulated carbon-steel process piping. Couples Fourier heat conduction through the insulation annulus, Philip-de Vries hygrothermal moisture transport driven by capillary and thermal gradients, and Butler-Volmer electrochemical corrosion kinetics at the steel surface. All three fields are advanced together via Strang second-order operator splitting. A DFOS-informed inverse problem recovers moisture source magnitude and location from outer-cladding temperature observations.

Anchored to AMPP 2022 (CUI causes ~60% of refinery pipe leaks), API RP 583 critical temperature window (50-175C), and PHMSA Docket 2026-1520 (April 24, 2026). 151 tests, 5 analytical benchmarks.

Files

felipearocha/integrity-code-series-week9-cui-v1.1.1.zip

Files (77.7 kB)

Additional details

Related works

Is supplement to
Software: https://github.com/felipearocha/integrity-code-series-week9-cui (URL)

Software

Repository URL
https://github.com/felipearocha/integrity-code-series-week9-cui

References

  • API RP 583 (2014). Corrosion Under Insulation and Fireproofing.
  • Philip J.R., de Vries D.A. (1957). Moisture movement in porous materials under temperature gradients. Transactions, AGU 38(2): 222-232.
  • Strang G. (1968). On the construction and comparison of difference schemes. SIAM J. Numerical Analysis 5(3): 506-517.
  • AMPP (2022). Corrosion Under Insulation Industry Survey.
  • PHMSA Docket 2026-1520 (April 24, 2026). External corrosion threats on hazardous liquid pipelines.