SP-100 GES/NAT IHX design and development

The primary heat transport system (PHTS) equipment for the SP-100 ground engineering system (GES) nuclear assembly test to be conducted is discussed. The heat transport system functions as a nonprototypical lithium primary system, transferring reactor heat to a sodium secondary system by means of the intermediate heat exchanger (IHX). The design and development of the IHX is described. Due to the system arrangement, the IHX must be designed to operate with a very large temperature difference between its primary and the secondary side, resulting in the need to use double-wall heat exchanger tubing in the selected U-shell/U-tube design. The differential thermal expansion in the unit resulting from the secondary and the primary system temperatures must be taken into account in the design. >