Title:	Development of effective models and validation against PPOOLEX and PANDA tests
DNr:	NAISS 2023/22-1337
Project Type:	NAISS Small Compute
Principal Investigator:	Xicheng Wang <xicheng@kth.se>
Affiliation:	Kungliga Tekniska högskolan
Duration:	2023-12-11 – 2025-01-01
Classification:	20306
Keywords:

Abstract

Steam injection into a large water pool is widely applied to Light Water Reactors (LWRs) to prevent overpressure of the primary and secondary. Direct contact Condensation (DCC) in a subcooled pool creates the sources of mass, heat, and momentum determined by the condensation regimes. Thermal stratification occurs if the heat source balances the momentum source, and it is regarded as a safety concern since the pool volume as the heat sink is reduced. Modeling of steam injection and its effect on a large pool is computationally expensive due to the considerable spatial and temporal scale differences between the steam-water interface and global pool circulation. To enable the prediction of such transient over a long period, Effective Heat Source (EHS) and Effective Momentum Source (EMS) models are proposed. These models aim to establish a correlation between the time-averaged integral effects of heat and momentum sources and the steam injection conditions without resolving the interface behaviors during condensation. This work aims to further develop EHS/EMS models using updated closures from recently performed Separate Effect Tests (SEF-POOL) and implement in CFD code (ANSYS Fluent). Model validation will be done against several integral pool experiments conducted in PPOOLEX and PANDA facility.