Details

Autor(en) / Beteiligte

• Magne, Sylvain
• Nehr, Simon
• Buet, Xavier
• Bentaïb, Ahmed
• Porcheron, Emmanuel
• Grosseuvres, Romain
• Studer, Etienne
• Scarpa, Roberta
• Abdo, Daniele
• Widloecher, Jean-Luc
• Norvez, Olivier
• Chaumeix, Nabiha
• Dhote, Julien
• Freyssinier, Mathilde
• Ruffien-Ciszak, Audrey

Titel

In\ situ$ gas monitoring by fiber-coupled Raman spectrometry for H$_2$-risk management in nuclear containment during a severe nuclear aAccident

Ist Teil von

• IEEE transactions on nuclear science, 2020-04, Vol.67 (4), p.617-624

Ort / Verlag

Institute of Electrical and Electronics Engineers

Erscheinungsjahr

2020

Link zum Volltext

Quelle

IEEE Xplore

Beschreibungen/Notizen

• During a severe nuclear accident leading up to core melting, molten corium-concrete interaction (MCCI) and core-coolant water reaction both release large amounts of hydrogen (H$_2$ ) gas in the containment atmosphere. According to the Shapiro-Moffette ternary diagram and depending on local partial pressures of H$_2$ , air, and water vapor, deflagration/detonation may occur with potential deleterious impact over equipment and structures. CO and CO$_2$ are also of interest, as revealing gases for MCCI. Pressurized Water Reactors (PWRs) of French Nuclear Power Plants (NPPs) are equipped with passive autocatalytic recombiners (PARs), partly mitigating the H$_2$ risk. However, the H$_2$ -risk management strategy may be significantly improved by performing in situ monitoring of H$_2$ , O$_2$ , N$_2$ , H$_2$O, CO, and CO$_2$ partial pressures at several locations inside the containment, to account for potential local combustion risk. Raman spectrometry (RS) involves only one laser and spectrometer equipped with a 2-D charge-coupled device (CDD). Raman probes are chemically selective and may be radiation-hardened. Custom-made fiber-coupled Raman probes, linked with a readout unit, were qualified in a climatic chamber, a flame-propagation tube, a $^{60}$Co irradiation cell, a 3-D shaking table, a steam jet and the MISTRA facility (1/10 reduced-scale containment mock-up dedicated to thermo-hydraulic tests).