Magnetization and d/sub eff/ in multifilamentary Nb/sub 3/Sn strands

The magnetization of various design internal-Sn type Nb/sub 3/Sn strands was analyzed in terms of effective filament diameter, d/sub eff/. Assuming circular geometry and ignoring demagnetization, values of d/sub eff/ have been calculated numerically for various configurations including unsplit subelement and split subelement cases with 2, 3, 4 and 6 splits. In the numerical calculation, the magnetization was treated as the summation of the magnetization of sections aligned perpendicular to the applied field. The angle-averaged d/sub eff/ value was calculated for every degree over the split regions. The d/sub eff/ of single restacked strands using subelements with various numbers of splits has been calculated and the results show the influence of the split design of strands on the magnetization in high fields. Furthermore, the numerical results were compared with the reported simplified analytical results, about 20% difference indicates the approximation of the simplification.