Development and validation of the MAVR-TA code for analyzing the release and transport of fission products during a severe accident at a nuclear power plant with VVER. Part 1 – Release of fission products from a fuel

Abstract This paper provides information on the development and validation of the MAVR-TA code. The MAVR-TA code is designed to simulate the fission products release from fuel and melt, and the transfer of fission products in the primary circuit and in the containment during a severe accident at NPP with VVER. The first part of the work provides information on the models of the MAVR-TA code, associated with modeling of the fission products release from the fuel. The paper provides information about description of the models and their approaches. In addition, it provides a description of the experimental tests, which were used to validate the models of the fission products release in the MAVR-TA code. As a result, the applicability of the models for calculating the fission products release from UO2 and MOX fuel has been demonstrated.