An evaluation of designed Start-up System (SUS) for once-through steam generators

Highlights: • Four SUS solutions are established to help reactors complete the start-up process. • Solutions C and D lead to superior behaved than Solutions A and B. • Solution C is fit for propulsion reactors and Solution D for nuclear power reactors. - Abstract: In this paper, we report on research that has been carried out both on the comparison and evaluation of four designed Start-up Systems (SUSs), which are proposed to improve reliability and economy during the reactor start-up process. Firstly, four SUS solutions are established to satisfy demands and detailed descriptions are introduced. Then, four reactor systems, which include SUS, are modeled by the estimate code JTopmeret. Furthermore besides, the JTopmeret code is validated for the once-through steam generators (OTSG). Finally, the behaviors of SUS and the steady and transient performance of OTSG are investigated. The results show that the designed SUS can successfully improve the economy and the OTSG operational safety. Suggestion is made in this paper to apply Solution C in propulsion-purposed reactors, and Solution D in nuclear power reactors