Pressure drop calculation of gas path for heat treatment system of Nb3Sn superconducting coils

Heat treatment system specialized for Nb3Sn superconducting coils has been developed and has completed at High Magnetic Field Laboratory, Chinese Academy of Sciences (CHMFL). The model coil has been heat treated with Ar gas flowing in the Cable-in-Conduit Conductor (CICC). Empirical equations are used to calculate the pressure drop of Ar gas between the inlet and outlet of the gas path system and the results shows that the pressure drop strongly depends on the flow rate, pipe length, and heat treatment temperature. Experimental results are also presented in the paper and it agreed with the results we calculate and simulate.