To cool down the detectors of the Large Hadron Collider, namely ATLAS and CMS, a R744-R744 cascade system is needed having a primary 2-stage compression loop on the high pressure side and a pumped, oil-free low-pressure loop on the evaporation side. The primary refrigeration system is used to guaranty the pump of the secondary loop a stable 10K sub-cooling. Two demonstration plants (System A & B) are built to evaluate the control logic and oil management before the cooling system is built on-site. Field and simulation data of System A are analyzed to evaluate the systems control logic. This work presents the experimental results obtained for a modular, trans-critical demonstration plant "System A" at CERN (DEMO). The experimental tests are carried out to analyze the systems control logic to guarantee a stable and reliable operation on the final system. Furthermore, it presents simulation results obtained for a modular, trans-critical demonstration plant "System A" at CERN (DYM). Simulations are done to validate the experimental results. The simulation of the demonstration plant explores the systems control logic adopted to manage two vapour compressor modules.

Dymola, 2020x

TIL, 3.11.0

TILMedia, 3.11.0

DaVE, 1.7.0

MATLAB, R2019a