Simulation and verification of air cooling system for -1MVdc MITICA High Voltage hall in Padova

Highlights: • Integration of an high voltage test facility (−1 MV), air insulated, in a dedicated building. • The paper covers the aspects of integration between the high voltage deck ventilation system and the civil air conditioning system. • The focus of the paper is the CFD simulation of the two coupled sub-systems, from the hypothesis to the results, also considering possible simplifications and realistic operational scenarios. -- Abstract: The first ever built full-scale prototype of the ITER heating neutral beam injector is the MITICA experiment at PRIMA-NBTF (Neutral Beam Test Facility), under realization in Padua, Italy. The MITICA experiment includes many auxiliary plants; this paper is focused on the simulation and verification of the air cooling system of the High Voltage Power Supply (−1 MVdc), hosted in a Faraday cage (HVD1, High Voltage Deck1) inside a dedicated Building (High Voltage Hall, HVH) at PRIMA-NBTF. The HVD1 hosts the MITICA ISEPS (Ion Source Power Supply) in a two-floor cage, air insulated to ground for -1MVdc, with huge dimensions 12.5 m (L) × 8.4 m (W) × 9.6 m (H). Severe cleanliness constraints are required in the HVH hosting the HVD1, due to the high voltage operative conditions (the −1 MVdc Faraday cage is air insulated). The thermal behavior and air distribution in HVH are investigated as described in this paper.