Numerical quench simulation for a superconducting generator

A numerical simulation procedure QSLM is described, which calculates transients of hydrodynamic and thermodynamic quantities in the rotating helium system of an ac-generator with superconducting field windings, following an energy input into the coil. The model comprises the helium transfer unit, the winding with radial cooling channels, a central subatmospheric bath and a selfpumping exhaust system. The properties of conductor and coolant, flow dependent heat transfer, friction and acceleration effects are taken into account in onedimensional approximation. Results are presented for a full quench in the Superconducting Rotor Model presently designed at KWU/ Siemens. Large internal and external mass flow rates and oscillating flow in parallel cooling channels is observed. Pressure build up is limited to 13 bar on the rotor axis, the temperature in the conductor attains 85 K, blow out of helium takes place mainly via the helium transfer unit.