Computational investigation on thermohydraulic characteristics of High-Temperature Superconducting (HTS) power cables

Abstract

High-Temperature Superconducting (HTS) cables are emerging as an effective alternative for conventional power transmission system in reducing transmission losses, electrical impedance and Right-of-Way (RoW). Rare earth based superconducting tapes such as Bismuth strontium calcium copper oxide (BSCCO-2223) and Yttrium barium copper oxide (YBCO-123), whose critical temperatures are 110 K and 90 K respectively, are preferred in manufacturing of HTS cables, due to their potential to handle high current load, in cryogenics environment. Moreover, for retaining the superconductivity, these HTS tapes are preferably cooled by Liquid Nitrogen (LN2) (boiling point ∼77 K), in order to remove the heat flux from different sources such as AC losses in HTS tapes, heat-in-leak due to axial conduction through the current leads and radial heat-in-leak from the ambient through the insulation. Therefore, it is essential to estimate the cooling capacity of HTS cables and associated pumping power required for circulation of LN2 between end terminations. Hence, in the present work, the thermohydraulic analysis relevant to the design of long length HTS cables is presented. The computational model of LN2 flowing through corrugated pipe of HTS cable is developed, followed by the estimation of pumping power and cooling capacity, using the commercial code FLUENT. The obtained results are validated with the experimental measurements available in literature.