Heat Diffusion in high-$C_p$ Nb$_3$Sn Composite Superconducting Wires

TL;DR

This paper investigates heat diffusion in high-$C_p$ Nb$_3$Sn superconducting wires, using finite element modeling to compare advanced and standard wire designs, aiming to enhance thermal stability and reduce magnet training.

Contribution

It introduces a finite element model for heat diffusion in high-$C_p$ Nb$_3$Sn wires and compares model predictions with experimental measurements, highlighting potential improvements in magnet stability.

Findings

High-$C_p$ wires show improved thermal stability.

Model predictions align with experimental MQE measurements.

Advanced wire designs could reduce magnet training.

Abstract

A major focus of Nb$_3$Sn accelerator magnets is on significantly reducing or eliminating their training. Demonstration of an approach to increase the $C_p$ of Nb$_3$Sn magnets using new materials and technologies is very important both for particle accelerators and light sources. It would improve thermal stability and lead to much shorter magnet training, with substantial savings in machines' commissioning costs. Both Hypertech and Bruker-OST have attempted to introduce high-$C_p$ elements in their wire design. This paper includes a description of these advanced wires, the finite element model of their heat diffusion properties as compared with the standard wires, and whenever available, a comparison between the minimum quench energy (MQE) calculated by the model and actual MQE measurements on wires.