Energy margin of cable-in-conduit conductor as a function of operating pressure and initial heated zone

The intrinsic properties of low temperature helium exhibit strong variations with changes in pressure and temperature. As a result, important design parameters such as the energy margin of superconductors in the cable in conduit configuration is a strong function of the initial operating conditions. Since the energy margin of CICCs is dominated by the available helium enthalpy, the dependence of the energy margin on initial conditions can be derived from an examination of the helium properties. For superconductors operating in the range of 6 to 8 K, the energy margin can be improved by a factor of three with a suitable choice of initial operating pressure. Other factors effecting the energy margin include the length of the initial heated zone, and the length of the heating pulse.