Introduction

This chapter looks at a brief history of sodium-cooled fast reactors starting from the basics of breeding and bringing out the aspect of high uranium utilization in fast reactors. It briefly describes the components of a sodium-cooled fast reactor and lists the experimental and prototype fast reactors in the world. The future reactor concepts being pursued, namely GEN IV, of which fast reactors are the most widespread concept, are presented. The role of dynamic simulation in assuring safety and setting up the safety logic thresholds for an automatic reactor trip, thus ensuring an assessment of the shutdown systems and decay heat removal, is presented. Dynamic simulation tools used by different countries in their fast reactor programs are presented.