23 Elements of thermal hydraulic design of water-cooled nuclear reactors

The present chapter deals with the thermal hydraulic design features of reactor coolant systems (RCSs) for selected categories of water-cooled nuclear reactors (WCNRs). Examples of questions in relation to which an answer is provided are: (a) Why is water adopted as a working fluid? (b) What is the reason for high pressure? (c) Why is thermal efficiency about 0.33 in current WCNRs? (d) What are the criteria for selecting the number of loops? (e) What is the basis for the design of emergency core cooling systems? (f) What are the key differences between boiling and pressurized water reactors (BWRs and PWRs)? (g) What are the key features of WCNRs which are neither PWRs nor BWRs? (h) What are the key features of thermal hydraulic passive systems? Specific sub-chapters are devoted to containment and balance of plant for those WCNRs. In the last section of the chapter, questions and answers are provided touching on the relevant parameters of WCNR design.