Modelling of quench in CICC with a central channel in the conduit

Abstract

This paper presents a theoretical model describing quench propagation in cable in conduit conductors (CICC) with an additional central flow channel. The central channel is used to enhance the flow capabilities in the conduit during steady state operation as well as during quench events. Such a system is the proposed design for certain conductors in the International Thermonuclear Experimental Reactor (ITER). Here, the additional channel is formed by a metal spring located at the center of the conduit. We describe the separate thermal evolution in both the cable bundle and the central channel; in particular, the mass, momentum and heat transfer due to flow between the cable bundle and the central channel are included in the model. Several simplifications are introduced which greatly reduce the complexity of the model without sacrificing accuracy. The resulting reduced model is solved both numerically and approximately analytically for ITER parameters.