The PMK-2 facility is located at the KFKI Atomic Energy Research Institute (AEKI), Budapest, Hungary. It is a full-pressure thermo-hydraulic model of the primary and partly the secondary circuit of the Paks nuclear power plant of VVER-44012 13 type. At the start-up time of 1985 PMK-2 was the first and the only integral-type facility for VVERs. It was designed and constructed to aid in the understanding of system behaviour and to provide databases for computer code validation. The PMK-2 was followed by the PACTEL facility for VVER-440 in Finland (1990) and the ISB and PSB facilities for VVER-1000 in Russia (1992 and 1998, respectively).

Since the start-up of the PMK-2 facility in 1985, altogether 55 experiments have been performed primarily in international framework with the participation of several experts from European and overseas countries to study one- and two-phase natural circulation, loss-of-coolant accidents (LOCA), special plant transients and accident management (AM) procedures. The results have been used for the validation of thermohydraulic system codes like ATHLET, CATHARE and RELAP5 for VVER applications.

A large number of integral-type tests have been performed in the past 30 years all over the world in different test facilities. In the last decade the OECD CSNI recognised that there is a tremendous danger of loosing these test results due to closing down many of these facilities, retirement of experts and changes in data storage. A huge effort was initiated in the 90s to collect the most important data included in the CSNI Integral Test Facility Validation Matrix at the NEA Data Bank - with limited success. In order to avoid this problem with respects to the PMK-2 data, the present book, the first volume of the final report of the PMK-2 projects, summarizes the experimental results.

The PMK-2 database has a significant value for the safety evaluation of the VVER-44012 13 type reactors in operation. The database provides a valuable source of scientific information to the nuclear community in the world. The 20 year operational period established an international scientific school for the experts of 29 countries participating in the PMK-2 projects.

Two further separate volumes are under preparation as follows:

• key findings for the safety evaluation of VVER-44012 13 type nuclear power plants;
• evaluation of the results of computer code validation obtained for RELAP5, ATHLET and CATHARE thermo-hydraulic system codes.

        

Last updated: 1 August 2007