Two-dimensional quench simulation of composite CuNb/Nb3Sn

In order to clarify effect of utilizing a Nb rich CuNb reinforment on super conducting stability, r-z two-dimensional time-dependent numerical simulati ons on composite CuNb/Nb3Sn wires are conducted. The time variations of tem perature and current density distributions, minimum quench energy (MQE), an d normal zone propagation velocity (v(p)) of a Cu-17vol%Nb/Nb3Sn wire, a Cu -63vol%Nb/Nb3Sn wire, and a conventional Cu/Nb3Sn wire are investigated. Th e increase of the volume fraction of an outermost Cu stabilizer provides hi gh MQE but decreases the total current density. Although the v(p) is not si gnificantly influenced by the Nb fraction, the Nb rich CuNb reinforcement s acrifices the MQE for its high tensile strength. It is important for magnet design to control the volume fraction of the Cu stabilizer and Nb fraction in the CuNb reinforcement to balance the desired current density, tensile strength, and superconducting stability. (C) 2001 Elsevier Science Ltd. All rights reserved.