Investigation of fires in a mechanically ventilated compartment using the CFD code FireFOAM
Résumé
The outbreak of fires in nuclear power plants is a major risk due to the potential leak of radioactive materials. The use of traditional prescriptive fire safety regulations has shown its limitations and there is now a shift towards performance-based fire safety engineering, which requires well validated fire models. Nuclear power plants require the use of mechanical ventilation, which provides the dynamic confinement for the nuclear materials by maintaining the required pressure. During a fire, there is a possibility of pressure variations within the power plant which modifies the confinement level leading to the loss of the dynamic confinement and the escape of nuclear materials.
The current study aims to build on existing research by making use of an emerging open source computational fluid dynamics (CFD) fire simulation code known as FireFOAM, to predict fire behaviour in a mechanically ventilated nuclear compartment. An existing in-house modified version of FireFOAM developed by authors’ research group, is modified in the present work to include conjugate heat transfer in order to account for the heat transfer between combustion gases and solid boundaries. Moreover, a mechanical ventilation model has been developed and implemented into FireFOAM. This newly modified version of FireFOAM is employed to predict the pressure variations in a nuclear compartment and the flow rates in the ventilation network. The predictions are compared to some experimental data from the open literature. Overall, it is shown that the mechanical ventilation model and the modified FireFOAM can predict the pressure variations and flow rates with a relatively good level of accuracy.
Domaines
Sciences de l'ingénieur [physics]
Origine : Fichiers produits par l'(les) auteur(s)
