Temperature distribution along superconducting power transmission lines

A system of equations, describing the refrigerant's parameters (temperature and pressure) change, during its flow along a heated pipeline, for example along a superconducting power transmission line (SPTL), is derived.The possibility of a temperature maximum existing in the SPTL is found.The possibility, in principle, of ‘isothermal’ SPTL (with constant temperature, along its length) is shown. The most favourable refrigerant parameters' region for SPTL is determined.