The first comparison of the seventh AER Dynamic Benchmark problem results obtained by RELAP5-3D and DYN3D/ATHLET computing codes


The first comparison of the seventh AER Dynamic Benchmark problem results obtained by RELAP5-3D and DYN3D/ATHLET computing codes

Bencik, M.; Hadek, J.; Kozmenkov, Y.; Kliem, S.

The paper gives the first comparison of the 7th three-dimensional AER dynamic benchmark calculation results received with the codes RELAP5-3D (ÚJV) and DYN3D/ATHLET (HZDR). This benchmark was defined by A. Kotsarev, M. Lizorkin and R. Petrin at the 20th AER Symposium in Hanassari (Finland). It is focused on investigation of transient behavior in a VVER-440 nuclear power plant. Its initiating event is the opening of the main isolation valve and re-connection of the loop with its main circulation pump in operation. A water slug with lower temperature of 100 K enters the core which leads to a reactor power excursion. The activation of the reactor scram is caused by the corresponding power level signal. As a result of the scram, the turbines are turned-off by closure of the turbine isolation valves. All main circulation pumps remain in operation. Each participant had to use its own developed input plant data deck and parameterized library of macroscopic cross sections. The VVER-440/213 plant is at the end of the first fuel cycle and in hot full power conditions. The initial reactor power tuning and burnup calculations were performed with the code DYN3D by both participants. The first part of paper contains a brief description of RELAP5-3D and DYN3D/ATHLET system codes, their NPP input decks and reactor core models. The second part shows the comparison of important global and local time dependent parameters. The trends of main calculated parameters are very close. The calculated nuclear and thermal-hydraulic phenomena like reactor power, cold leg mass flow rates, cold and hot leg coolant temperatures, upper plenum pressure, pressurizer water level and steam generator powers agree quite well.

  • Contribution to proceedings
    22nd Symposium of Atomic Energy Research (AER) on VVER Reactor Physics and Reactor Safety, 01.-05.10.2012, Pruhonice, Czech Republic
    Proceedings of the 22nd AER Symposium, Budapest: MTA Energoatom, 9789635086276, 653-675

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Publ.-Id: 18322