ISSN Online: 2688-7231
ISBN Flash Drive: 978-1-56700-497-7
ISBN Online: 978-1-56700-496-0
Proceedings of the 25th National and 3rd International ISHMT-ASTFE Heat and Mass Transfer Conference (IHMTC-2019)
NUMERICAL SIMULATION OF FLOW BOILING OF LIQUID SODIUM IN A NARROW VERTICAL ANNULUS SIMILAR TO THAT OF SFR FUEL SUBCHANNEL
The Sodium cooled Fast Reactor (SFR) is a generation IV nuclear reactor which uses fast neutrons for fission and liquid sodium as the coolant for fission heat removal. Compared with the conventional fluids, such as water, liquid sodium shows superior performance in heat transfer because of its high thermal conductivity and low Prandtl number. So it is important to have proper understanding of two phase flow heat transfer characteristics of liquid sodium under certain postulated accidental conditions of SFR. The computational fluid dynamics (CFD) simulation of two phase flow heat transfer processes in liquid sodium have been performed for a narrow annulus channel that has resemblance with the flow subchannel of SFR fuel subassemblies. The Eulerian-Eulerian multiphase model with non-equilibrium wall-boiling model for wall heat flux partitioning is considered for the simulation. The liquid turbulence is modelled using Realizable k-ε model with standard wall function. This paper describes the typical liquid sodium flow boiling characteristics obtained from these simulations. This include the boiling inception to near quasi-steady flow boiling condition and further the pulsating type boiling behaviour and under this condition the two-phase flow pattern will be from its subcooled nucleate boiling to saturated boiling regime. So development of a model to capture two phase flow characteristics in SFR safety analysis using FVM based CFD software is the scope of this study.