Nuclear reactor core material molten pool evolution characteristic analysis method based on particle method

Abstract

The invention discloses a nuclear reactor core material molten pool evolution characteristic analysis method based on a particle method. The method mainly comprises the following steps: 1, modeling ageometric model; 2, initializing physical properties; 3, calculating a kernel function and particle number density between particles; 4, calculating a substance mixing process, and updating the content, enthalpy value and physical property of the particulate matters; 5, calculating a chemical reaction process, and updating the content and enthalpy value of the particulate matters; 6, calculating aheat transfer process, and updating a particle enthalpy value; 7, calculating the particle temperature and the phase state according to the enthalpy value; 8, explicitly calculating a viscosity itemand a gravity item; 9, explicitly calculating a turbulence stress term, estimating particle speed and position, calculating a turbulence heat flow term, and updating a particle enthalpy value; 10, carrying out implicit iterative computation on the particle pressure; 11, correcting the speed and position of the particles according to the pressure value; and 12, outputting a calculation result. According to the method, all phenomena in a nuclear reactor core material molten pool are considered; and based on a particle method, substance changes, phase state changes and flow characteristics in a molten pool can be accurately captured.

Description

technical field [0001] The invention relates to the technical field of analysis and research on the evolution characteristics of molten pools of nuclear reactor core materials, in particular to a method for analyzing the evolution characteristics of molten pools of nuclear reactor core materials based on particle methods. Background technique [0002] During the operation of a nuclear reactor, if the coolant cannot completely remove the heat generated by the core, the core will deviate from the normal operating conditions. In severe cases, the temperature of the core will rise sharply or even melt. During the melting process of the core, the material in the core with a lower melting point or capable of chemical reaction will be preferentially liquefied. At about 800°C, the silver indium cadmium alloy melts; at about 940°C, the iron-zirconium and nickel-zirconium eutectic reaction forms a liquid eutectic product; at about 1150°C, boron carbide and iron undergo a eutectic reac...

AI Technical Summary

Problems solved by technology

At present, there are few studies on the change of the melt pool structure when the core melt reacts with concrete. A large number of experiments focus on the concrete ablation rate and cooling mitigation measures. Differences in the Ablation Behavior of Concrete by Pools and Single Melts

The numerical simulation of this process is also difficult, most of which simplify the consideration of the influence of the multi-layer molten pool, and cannot reproduce the change of the molten pool structure caused by the change of the melt composition.

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