INVESTIGATION OF THE MIXING OF COOLANT FLOWS IN A VVER VESSEL

摘要

The mixing of flows in a flow-through channel of a WER-1000 reactor in the case where a flow with high or low boron concentration and a flow whose temperature is different from the temperature in the reactor are fed into the same circuit is studied. To this end, investigations were performed on a bench at Gidropress Special Design Office with a model WER-1000 reactor on a 1:5 scale. Regimes with the main circulation pump switched on and with natural circulation restored for an accident with a small leak are studied. Intercircuit mixing in the WER-1000 reactor setup is also studied in the case where the temperature of the coolant changes in one of the circuits (regimes with a break in a steam pipe and closure of the steam channel of the turbine) or with asymmetric feeding of boron into the first loop when one of the tanks in the system for rapid introduction of boron fails. An analytical solution of the problem and the results of measurements performed on units with WER-1000 reactors are presented.