Infrastructure > Experimental Devices > BWR-2


Smyčka BWR-2

The experimental water loop BWR-2 is used for the material research of BWR type reactors under conditions simulating the operation of BWR reactors (pressure, temperature, radiation, fluid analysis).

Nominal parameters

Pressure 12 MPa
Temperature 300 °C
Flow rate of primary circuit 8000 kg/h
Flow rate of purification circuit 400 kg/h
Working fluid ultrapure water
Amount of water in primary circuit 0.420 m3
Amount of water in whole loop 0.510 m3


The loop consists of a closed pressurized circuit with forced water circulation in the test irradiation channel K2 located next to the LVR-15 reactor core and in out-of-pile channel K3 located outside the neutron radiation field in the machine hall. Two 50 CT specimens provided with a notch and loaded with a cyclic stress of 151.7 kN in periods lasting 28 to 32 hours are placed in the K2 irradiation channel. During mechanical load the specimen is exposed to the effects of neutron flux and water flow. Physical and chemical conditions of the specimen exposure in the channel are close to operational conditions inside the boiling water reactors where the tested materials will be used. During the experiment, the size of the developing crack and its spreading is measured continuously.

The K3 reference channel where the two 50 CT specimens are located is connected to the loop. The above specimens are exposed to the same mechanical load as the specimens inside the K2 irradiation channel. The above specimens, however, are not exposed to the effects of radiation and the content of H2O2 is lower then in the K2 channel. The remaining physical and chemical parameters are the same in both channels. By comparison of measured results of the specimen in both channels, the effect of irradiation on the corrosion process and crack spreading can be evaluated.

BWR-2 Loop Chart

BWR-2 Chart

1 main circulation pump;
2 heater;
3 H2O2 generation channel;
4 in-pile channel;
5 out-of-pile channel;
6 regeneration exchanger;
7 cooler;
8 mechanicl filter;
9 conductivity measurement;
10 mixed-bed filter;
11 H2 and O2 concentration measurement;
12 pressure gas bottle;
13 vessel for chemicals dosing;
14 H2 and O2 dosing;
15 pressurizer;