Adiabatic calculation of quench temperature--A simple method for dimensioning the protection circuit of a superconducting magnet

The quenching of superconducting coils is one of the operating conditions to be considered. It determines the design of the protection circuit and, possibly, the cryostat. It is however extremely difficult to calculate the complete quench event. A theory is presented here where the conductor heating by resistive power is calculated assuming adiabatic conditions. The differential equation resulting is integrated to form a function from which the final temperature of the hot spot and the final energy balance can easily be obtained for an individual magnet configuration. Because heat conduction, heat transition to the helium and the effect of eddy currents have been ignored, this result only allows a worst-case-design where a magnet dimensioned in accordance with this simple method must always be on the safe side.