ITER Side Correction Coil Quench model and analysis. (December 2016)

• Record Type: Journal Article
• Authors: Nicollet, S.; Bessette, D.; Ciazynski, D.; Duchateau, J.L.; Gauthier, F.; Lacroix, B.
• Is Part Of: Cryogenics. Volume 80:Part 3(2016)
• Page Start: 305
• Page End: 316
• Publication Date: 2016-12
• Subjects: Cable-In-Conduit Conductors -- Thermohydraulics -- Fusion Magnets -- Quench simulation -- Quench codes benchmarking; Low temperature engineering -- Periodicals; Low temperature research -- Periodicals; 536.56
• DOI: 10.1016/j.cryogenics.2016.06.005
• Languages: English
• ISSNs: 0011-2275

Abstract

Highlights: Quench thermo-hydraulic studies on the ITER Side Correction Coil. Model with SuperMagnet Code with four parallel pancakes and one cryogenic circuit. Simulations and secondary thermohydraulic detection for undetected quench (Δ V ). Evaluation of hot spot temperature and comparison to the design criterion of 150 K. Abstract: Previous thermohydraulic studies performed for the ITER TF, CS and PF magnet systems have brought some important information on the detection and consequences of a quench as a function of the initial conditions (deposited energy, heated length). Even if the temperature margin of the Correction Coils is high, their behavior during a quench should also be studied since a quench is likely to be triggered by potential anomalies in joints, ground fault on the instrumentation wires, etc. A model has been developed with the SuperMagnet Code (Bagnasco et al., 2010) for a Side Correction Coil (SCC2) with four pancakes cooled in parallel, each of them represented by a Thea module (with the proper Cable In Conduit Conductor characteristics). All the other coils of the PF cooling loop are hydraulically connected in parallel (top/bottom correction coils and six Poloidal Field Coils) are modeled by Flower modules with equivalent hydraulics properties. The model and the analysis results are presented for five quench initiation cases with/without fast discharge: two quenches initiated by a heat input to the innermost turn of one pancake (case 1 and case 2) and two other quenches initiated at the innermost turns of four pancakes (case 3 and case 4). In the 5th case, the quench is initiated at the middle turn of one pancake. The impact on the cooling circuit, e.g. the exceedance of the opening pressure of the quench relief valves, is detailed in case of an undetected quench (i.e. no discharge of the magnet). Particular attention is also paid to a possible secondary quench detection system based on measured thermohydraulic signals (pressure, temperature and/or helium mass flow rate). The maximum cable temperature achieved in case of a fast current discharge (primary detection by voltage) is compared to the design hot spot criterion of 150 K, which includes the contribution of helium and jacket.