Thermal-hydraulic modeling of reactivity accidents in MTR reactors

Abstract

This paper describes the development of a dynamic model for the thermal-hydraulic analysis of MTR research reactors during a reactivity insertion accident. The model is formulated for coupling reactor kinetics with feedback reactivity and reactor core thermal-hydraulics. To represent the reactor core, two types of channels are considered, average and hot channels. The developed computer program is compiled and executed on a personal computer, using the FORTRAN language. The model is validated by safety-related benchmark calculations for MTR-TYPE reactors of IAEA 10 MW generic reactor for both slow and fast reactivity insertion transients. A good agreement is shown between the present model and the benchmark calculations. Then, the model is used for simulating the uncontrolled withdrawal of a control rod of an ETRR-2 reactor in transient with over power scram trip. The model results for ETRR-2 are analyzed and discussed

Research on manoeuvring capabilities of a nuclear power plant when switching in-use control programmes

“…The development of new methods to control the NPP and to increase its safety was relevant and valid, but none of the suggested methods included the switching of power control programmes at the reactor unit being in operation. Study [11] described the development of a dynamic model for a thermal-hydraulic analysis of materials test reactors (MTRs) during a reactivity insertion accident. A static reactive compensator (SRC) was studied to analyse the effect on the problem of load flow of a power system [12].…”