MS student Jianqiao (Peter) Xiao with Advisor K. Haran 

In previous research, a spoke-suspension system was designed to lower thermal conduction in a cryogenic rotor so that a superconducting rotor can be cooled by a cryocooler. The details of the spoke-supported rotor, including spoke attachment, cryocooler mounting, and cooling through conduction are studied and some preliminary methods have been proposed. Figure 4 shows the complete assembly of a subscale model. Meanwhile, because the rotor design involves a cryocooler working under high-speed rotation, a rotating cryocooler test has been designed and carried out to study whether the cryocooler performance is affected by the rotation. A preliminary result shows that strong vibration occurs at about 300 rpm and the no-load temperature reaches 40 K under vacuum. Further experiments will be conducted to mitigate the vibration and to improve sealing of the vacuum chamber for high-vacuum test.

Figure 4. Sub-scale model of a spoke-suspended superconducting machine