Analysis of throttle component resistance characteristic of steam generator

The steam generator of sodium-cooled fast reactor (SFR) designed by straight tube structure is one of the significant heat transfer equipment, for which the coolant liquid metal sodium flow through the shell-side, and the water/steam flow is located at tube-side. When water is heated to superheated steam, it inevitably experiences boiling and heat transfer deterioration process. In tube-side of steam generator, it will occur two-phase flow instability phenomenon which may cause series of operational and safe issues. In order to prevent the two-phase flow instability phenomenon, there are two following methods: one is installing throttle component at the inlet of the heat exchange tube, or installing mixed equipment in the evaporation section of the heat exchange tube. For limited steam generator structure, this paper puts forward adopting throttle component at the inlet of the heat exchange tube, and design a CFD model, simulating the influence of characteristic size, high temperature condition and flow velocity to the resistance characteristic of throttle component. The above summarizes the main influence factors of resistance coefficient, and finally to provides a theoretical basis for optimizing the throttle component structure design. (authors)