The MITICA Facility: A Possible Optimization of the Cryogenic Plant Cooling Capacity

In MITICA experiment (Padova, Italy), a large sorption cryopump has to be installed in the Beam Line Vessel. A dedicated cryogenic plant has to be realized to supply the cryopanels with ScHe @ 4.6 K and GHe @ 80 K for radiation shields. Considering the various operation modes of MITICA cryopump, a possible way to decrease significantly the installed cryogenic power (referred to 4.6 K) is the use of a helium refrigerator sized on an average refrigeration power value instead of the peak heat load and constantly operating at full power. The additional refrigeration power requested during beam pulse operations would be supplied by LHe inside a Control Cryostat housing the heat exchangers that cool the cryopanels ScHe loop; the recovery of evaporated LHe can be carried out during the long regeneration time performed overnight. A test case of MITICA experiment in ITER conditions foresees fast cryopump regeneration, detailed in this paper.