Computational Sensitivity Study on Sodium-Water Reaction Phenomenon

Abstract

Sensitivity studies on Sodium-Water Reaction (SWR), which will take place in a steam generator of Liquid Metal Fast Reactor (LMFR) when a heat transfer tube fails, have been carried out using a multi-dimensional computational code: SERAPHIM. An initial pressure of liquid sodium, an interfacial area density and an evaporation of sodium hydroxide (NaOH) are chosen as a parameter in this study. An influence of the parameter on a development of high temperature zone (>1000°C) and maximum temperature has been investigated from the perspective that one avoids a secondary heat transfer tube failure in a steam generator due to overheating rupture. In the analyses, it is assumed that water vapor leaks into liquid sodium without any barrier for a simplicity. As a result, it is found that the initial pressure and the interfacial area density affect the high temperature zone strongly, whereas they have almost no influence on the maximum temperature in the present configuration. As concerns the evaporation of sodium hydroxide, it influences not on the high temperature zone but on the maximum temperature. The maximum temperature decreases approximately 200°C due to latent heat of the evaporation. It is concluded that the evaporation of sodium hydroxide will be a key phenomenon for maximum temperature investigation in the SWR.

KEYWORDS:

• computer fluid dynamics
• sodium-water reaction
• multi-phase analysis
• safety analysis
• liquid metal fast reactor