Speaker
Description
The first ever built full-scale prototype of the ITER heating neutral beam injector is the MITICA experiment at PRIMA-NBTF, under realization in Padua, Italy.
The MITICA experiment includes many auxiliary plants; this paper is focused on the integration of the High Voltage Power Supply (-1 MV), hosted in a Faraday cage (HVD, High Voltage Deck) inside a dedicated Building at PRIMA-NBTF.
The HVD hosts the MITICA ISEPS (Ion Source Power Supply) in a two-floor cage, ground insulated, with huge dimensions (11 m x 10 m x 9.5 m, LxBxH).
Most part (around 85%) of the heat load generated by ISEPS is cooled by a deionized water dedicated circuit, while around 100 kW are rejected to the air surrounding the equipment located in the Faraday cage.
Severe cleanliness constraints are required in the Building hosting the HVD, as caused by high voltage operative conditions (the -1 MV Faraday cage is air insulated).
A dedicated air-forced ventilation system is part of HVD procurement; this system has been integrated in the Building conventional air conditioning system (part of building Contract) by studying operative scenarios with a Computational Fluid Dynamics (CFD) tool, as well explained in this paper.
Different operating scenarios were analyzed with this tool in order to optimize the Building air conditioning system, to improve the positions of air inlet and outlet nozzles, to verify the system size, to check the efficiency of heat loads removal, and finally to investigate about possible zones with unacceptable air turbulence conditions.
Functional logics of the building conditioning system have been finally implemented both considering normal and exceptional operative conditions (like the intervention of fire extinguishing system of the insulation transformer located in the same Building).