Study On Cooling Process Of ADS Superconducting Magnet Horizontal Test

Nuclear power is clean and efficient. Currently the ADS system is the main approach to dealing with the nuclear disposal and improving fuel efficiency. ADS’ full name is accelerator-driven subcritical system and superconducting magnets are its internal extremely important componets. In order to meet the design requirements of the manufacture of superconducting magnets, it is needed to testify the magnets. The current work is to do a horizontal test, which is to testify the perfomance of superconducting magnets which appears in the actual position of the accelerator. This paper focuses on the ADS linac and its superconducting magnets’ horizontal testing process, and makes a further study on the current leads and cold shields of cryostat.Current lead is an important parts of the cryogenic system, it is a media of magnet excitation and it is very important to make a satisfying current lead. Except for current lead itsself, a flexible connection, thermal anchors, insulating material are also parts of the current lead module. This paper gives a proper sulution of the materials and structures of different components by numerical simulation. Furthermore, a theoretical analysis has been carried out to get the proper structure of current lead. This paper discovers that the current leads can work normally under 150% current by means of numerical simulation, which focuses on the heat load of current leads. The situation of the heat leakeage to the low temperature side which is under different current has been been studied, getting a relationship for predicting the heat leakage.The progress of cooling down the superconducting magnet needs a long time, an efficient and economical solution is needed.The cooling process of ADS superconducting magnet level test was simulated, and it shows that using refrigerator only is really difficult to cool down the magnet to 4.2K. It is found that cooling down the magnet by using liquid helium can reduce the magnet temperature rapidly. The relationship between liquid helium consumption with different initial temperature and its injecting mass flow has been studied. The rewarming condition of magnet during the accumulation of liquid helium has been analyzed by numerical simulation. Considering both helium and liquid helium cooling down methods, an optimized overall cooling down curve has been made. The overall time consumption is 17.58 hours, making this optimized method improve the efficiency greatly.Cold shied is extremely important within the cryosat, and radiant heat leakage is its major leak source. Studying the temperature and force on the cold shield by numerical simulation method, this paper discovers that using 6061-T6 aluminum with 2mm thickness as the cold shield is the most proper choice. Compared with cooling down results with different cold shield situations, it is found that adopting both 5K and 80 K cold shield is more advantagous than others.