Development of the high efficient and compact, next generation cooling system .

Purpose and Vision

The goal of this project is to develop a 2-phase CO2 cooling system, aiming at applications to the next generation large scale experiments, and to accumulate know-how for this new and promising technology.


Modern high energy physics experiments often require large scale detectors with millions of densely packed readout channels. For their high speed data acquisition, signal digitization at their front ends is now becoming common practice. The power consumption and consequently the heat load at the font ends are, thus, our serious concern from the view point of material budget for the detectors. Under such a circumstance 2-phase CO2 cooling is attracting attention as the technology of choice to realize an efficient and low mass cooling system.

2-phase cooling is the cooling with fluids in mixed states and makes use of the large latent heat for liquids vaporizing into gases or for solids melting into liquids, thereby achieving highly efficient extraction of heat with a low flow rate of the coolant fluids. It should also be emphasized that the the temperature of the coolant is determined only by the pressure and hence nearly constant along the cooling circuit, since the absorbed heat is used only for the phase transition.

2-phase CO2 cooling:a state change in cooling pipe ©Rey.Hori

Related Group

2-Phase CO2 Cooling System