Optimization method for superconducting magnet current leads

Current leads for superconducting magnets are studied to simplify the design into a single chart. A new parameter, obtainable with a brief calculation, is introduced. Characteristics of a wide variety of current leads, namely geometric dimension, heat flow into liquid helium and pressure drop of the cooling gas flow are represented in the form of a single design chart by using this parameter. Current leads can be optimized without explicit consideration of quantities such as cross-sectional area and length of conductor, heat transfer coefficient and cooling perimeter. As the burn-out of current leads is expected to occur with the accidental decrease or stoppage of cooling gas flow, this serious situation must be taken into account in the design. An adiabatic approximation is used to estimate the temperature rise. Further improvement of the performance can be obtained if the cross-sectional area decreases along the length of the conductor.