Fukushima Daiichi accidents led to the worldwide update of NPP safety requirements. Particular attention was paid severe both during design new units and reassessment existing ones. Performed operating focused on development implementation technical means strategies directed prevention and/or mitigation accidents. Technical solutions that are used in modern designs reactor facilities involve se...

The process of hydrogen formation and the associated risk combustion explosion is a complex problem concerned with radiation safety nuclear reactors. Lithium, potassium sodium hydroxides are used in VVER reactors as corrective additives for keeping potential water coolant boric acid at controlled level 5.8 to 10.3. In investigating interaction aqueous solutions above aluminum, most chemically a...

Iodine radionuclides in accident releases under severe accident conditions at NPP with VVER are the most radiationimportant with a view to population dose generation at the beginning of the accident. To decrease radiation consequences of severe accidents the technical solutions for severe accidents management have been proposed in MIR.1200 project, with consideration of the measures for suppres...

In this paper a detailed model of a VVER1000 reactor pressure vessel (RPV) with the extension of simplified primary loops is presented (Loop model). The primary loop components like steam generators and pumps are modelled by the outer shapes and additional source terms for energy and momentum exchange. The RPV model part is tested without primary loops and compared with former results obtained ...