Dynamic modelling of the advanced neutron source reactor : transient analysis and inertial flow diode concept

A study of the basic pressure and flow processes involved in the Advanced Neutron Source reactor dynamics is presented. The main topics of this research are the development of a computer program to model the ANS reactor and cooling system for dynamic simulation studies, the design of the new piping concept called inertial flow diode (IFD), and the design of several ANS cooling circuit components, particularly the vessel bypasses and the reflector tank. The most important result from the dynamic study is the survival of the reactor core under the worst inlet vessel double ended guillotine break when using the Inertial Row Diode piping concept. This concept can be extended to any pressurized water reactor. A flow and pressure dynamic study of a proposed reflector cooling circuit was performed using a dynamic model of the reflector cooling circuit. It was found that an accumulator located at the reflector outlet was needed to fulfil prescribed safety requirements. A dynamic study of heat load, coolant flow, and pressure in the reactor bypass region was performed which led to major improvements in the design of the control rod system. The work performed in this dissertation has resulted in a unified and validated general dynamic model of the ANS reactor suitable for the prediction of reactor transients generated by a variety of accident scenarios.