THERMAL DESIGN OF A HIGH-GRADIENT QUADRUPOLE FOR THE LHC INTERACTION REGIONS

The LHC high gradient quadrupole coils are subject to a continuous hea t load due to the beam-induced energy deposition during operation. All heat deposited in the coil must be removed so that the magnets will r emain in a superconducting state. The quadrupole magnets are designed to be cooled with stagnant pressurized He II. This paper summarizes th e heat flow analyses from the insulated coil to the boiling saturated He II for the LHC interaction region quadrupoles. The effects of cable surface heat nux and cooling channel heights on the thermal character istics of the magnets are studied. He II heat exchanger designs, arran ged internally and externally are compared.