Numerical Analysis of the Recooling of a LHC Sector from 30 K to 1.9 K following Resistive Transition of a Magnet String

To analyze the recovery process from a resistive transition of a magnet string of a LHC sector, a mathematical model is established based on the existing models describing the cooldown from 300 K to 1.9 K. In the new model, the number of magnet strings which undergo a resistive transition, as well as their location are considered. According to the analysis, the recovery process is optimized as well as the temperature evolution in the magnet cold-mass, the pressure profile in the very low pressure header during the recool-down process and the time used for the recool-down are presented.