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The paper contains the results of numerical simulation of stainless steel melt motions on the surface of uranium dioxide. The investigations are performed for purposes of understanding of the fuel rod behavior during the core disruptive accident in the fast reactors. The systems of mass, energy and momentum conservation equations are solved to simulate melt motion on the surface of the fuel pin. Heat transfer and friction between melt and pin's surface and melt and coolant flow are taken into consideration. The dependences of mass of the melt and the features of the melt motion on coolant velocity and contact angle between melt and surface of the fuel rod are presented.

The investigation of the melt flow of a liquid metal along the surface of a heated rod is carried up. In the experiments, the metal from the upper volume was drained over the surface of a quartz tube, heated from the inside. This pipe is used to simulate a fuel column. A high-speed video of the process was produced. Data are obtained on the features of the flow of a metal melt. The stages of formation of droplets are shown. The data on the shape and velocity of the droplet movement are given. It is shown that in the air atmosphere around the test section when the first drop passes on the surface of quartz, a trace is formed, along which the metal moves in the future. Direct and curvilinear rivulet flows on the rod's surface are also observed.

This paper describes the further development of the virtual flow meter concept based on the author's simulator of an unsteady gas–liquid flow in wells. The results of comparison with commercial simulators based on real well data are given as practical applications. The results of the comparison of the simulators demonstrated high correspondence (<10% error) for a number of target parameters. The description of the architecture and results of testing the algorithm for automatic settings of the model parameters are given. Operating speed was the key criterion in the architecture development. According to the test results, it became possible to achieve the adaptation accuracy of 5% specified. [ABSTRACT FROM AUTHOR]

The presented paper contains a description of approaches to simulate processes, observed during leakage in the steam generator of the reactor with liquid metal coolant. These approaches have been implemented in thermal hydraulic code HYDRA-IBRAE/LM. To calculate motion of gas bubbles in liquid metal flow and heat transfer of gas bubbles with metal, different relations are used in HYDRA-IBRAE/LM code. The code contains models of chemical interaction between water and sodium for modelling of tube rupture in sodium cooled fast reactors, Modelling of the experiments has been made using HYDRA-IBRAE/LM code. The results of the modelling with determined main factors are presented in the article.