Adapted FLASHCAT methodology to model horizontal cable tray fires using computational fluid dynamics

Nuclear power plants (NPPs) are a prominent energy provider in our present-day life. They have a massive network of combustible electrical cables to support daily operations. Any fire on such cables can affect the running of the safe operations of a NPP and can indirectly or directly cause damage to the nuclear reactor core which can lead to widespread damage. Assessment of the heat release rate (HRR) of cable fires is critical for the nuclear industry as HRR dictates the heat stress in the surrounding of a fire and other fire products which can affect the facility. Among many experimental campaigns conducted to understand cable fire behaviour, under the OECD (Organisation for Economic Co-operation and Development) PRISME-3 (French phrase: propagation d’un incendie pour des scénarios multi-locaux élémentaires) program, IRSN (Institut de Radioprotection et de Sûreté Nucléaire) conducted an experiment in which two cable trays were burnt in an open atmosphere to understand their fire behaviour. This paper presents a computational fluid dynamics-based method to replicate the experiment and model the HRR resulting from such cable fires through simulations. The method partly uses the FLASHCAT model and combines its modified form with the surface temperature ignition model of Fire Dynamics Simulator (FDS) software. The HRR obtained from the simulation had the time to reach peak HRR overestimated by 5 %, and peak HRR underestimated by 4 %. The result is encouraging as it provides confidence in using the modified adaptation of FLASHCAT model in CFD-based FDS software to predict HRR.