Cryogenic system design for HIAF iLinac

A helium cryogenic system is designed by the Institute of Modern Physics, Chinese Academy of Sciences, to supply different cooling powers to the cryomodules of ion-Linac (iLinac) accelerator, which serves as the injector of the High Intensity Heavy-Ion Accelerator Facility project. The iLinac is a superconducting heavy-ion accelerator approximately 100 m long and contains 13 cryomodules cooled by superfluid helium. This article describes the cryogenic system design of the iLinac accelerator. The requirements of the cryogenic system, such as cooling mode, refrigeration temperature, operating pressure and pressure stability, are introduced and described in detail. In addition, heat loads from different sources are analyzed and calculated quantitatively. An equivalent cooling capacity of 10 kW at 4.5 K was determined for the cryogenic system according to the total heat load. Furthermore, a system process design was conducted and analyzed in detail. Further, the system layout and the main equipment are presented.