Nuclear Energy and Scientific Support of Kozloduy Nuclear Power Plant (KNPP)

• Systems of models and procedures for investigations of long term development of national energetic

Calculated (curves) and measured ( signs) induced activities (neutron fluence) for Unit 1 of KNPP after 18-th cycle. (Courtesy Dr. T. Apostolov and Dr. K. Ilieva)
 

Advanced digital reactivity meter for KNPP, produced in INRNE

• Theoretical and experimental investigations on thermodynamics of high-temperature many-phase many-component systems and their application in reactor technologies
• Theoretical and experimental investigations on electro-corrosion processes of reactor materials
• Modelling and analysis of WWER fuel rod behaviour under normal operation of the KNPP Units I-VI
• Development, adaptation and validation of models and computer codes for thermo-mechanical analysis of WWER fuel rods
• Validation of the TRANSURANUS code system for WWER fuel rods

Experimental determination of the neutron fluence for WWER - 400 and WWER - 1000 reactors of KNPP: Shown is the mounting of neutron detectors behind the corps of Unit 6 of KNPP

• Assistance to the Safety Authority and KNPP in improving the fuel operational efficiency and safety by analyzing the fuel rod behavior at normal operational, transient and accident conditions, including regimes with extended burnup and new fuel rod design
• Development and modification of methods and computer codes for 3D thermal-hydraulic analysis of reactor core and nuclear reactors, related to nuclear safety
• Establishment and compilation of experimental data bases on thermal-hydraulical phenomena in nuclear reactors; validation and verification of developed methods and modified codes for nuclear reactors' analysis
• Thermal-hydraulic analysis of KNPP WWER-440 and WWER-1000 reactors; core safety margins definition for the real operation cycles, including transients' and accidents' analysis, changes in the fuel design, fuel assemblies design and/or fuel cycle
• Modeling of the fast transients and accidents in KNPP WWER reactors by coupled 3D neutron-kinetic/thermal-hydraulic computer codes
• Increasing the number of analyzed transients and accidents for KNPP WWER reactors: analyses of reactivity initiated accidents and anticipated transients without scram etc.
• Assistance to the KNPP neutron-physics calculation teams, in particular, with respect to main used computer codes CATHARE and COBRA
• Nuclear Safety Program for the KNPP, in cooperation with the U.S. Department of Energy within the framework of the International Nuclear Safety Program, include the US transfer of technology in the field of the Thermal-Hydraulic Analyses, using the computer code RELAP5 as well as the implementation of this program to KNPP with assurance of the hardware, software, documentation and US consultant. The Program permits KNPP to extend, perform and improve its safety analyses capability in the field of THA for WWER-1000/V-320 and WWER-440/V-230 reactor types, and especially for:
• Definition of initial and boundary conditions and accident scenarios
• Performing basic calculations
• Performing parametric studies
• Analyses and documentation of results.
• Neutron embrittlement and Lifetime assessment of VVER reactor pressure vessels by neutron fluence calculations. An original calculational and experimental neutron dosimetry methods have been developed and applied at KNPP for the Units 1-4 with VVER-440 and Units 5,6 with VVER-1000 (over 22 contracts with KNPP fulfilled).