Speaker
Description
The 'Surface Storage' module is one of the biggest (and most visible) changes to the Two-Phase Accumulator Controlled Loop principle, developed specially to deal with the requirements from CMS and ATLAS for the Hi-Lumi Phase-2 upgrade.
This 12 m3 surface storage vessel will store all the extra CO2 that cannot be stored in the cavern due to space constraints. Flow to/from the underground is done using a thermosiphon loop, relying on the buoyancy differences between the liquid CO2 going down and the two-phase CO2 coming up. The transfer piping on surface has been carefully sloped towards the underground to ensure an absence of vapour bubbles that can break the static liquid column and interrupt circulation.
In this talk, we present the commissioning status of the Surface Storage module for ATLAS. The different operating modes are discussed, along with the control philosophy and control system design for the module. Results from the early commissioning are shown and discussed.