Justification of measures aimed at ensuring the required fire resistance of structures enclosing NPP premises using CFD fire modeling

Introduction. The article presents a methodological approach to justifying measures designed to ensure the required fire resistance of structures enclosing NPP premises with the use of CFD (computational fluid dynamics) fire modeling. Approaches to justifying fire safety are considered using the fuel storage facility of an NPP standby diesel power plant as an example.

Aim. To develop and analyze the methodological approach to justifying measures designed to ensure the required fire resistance of structures enclosing NPP premises with the use of CFD fire modeling.

Materials and methods. The purpose and application scope of various methods for modeling fire dynamics was analyzed. Fire modeling used to justify measures for ensuring the required fire resistance of enclosing structures was considered using the fuel storage facility of an NPP standby diesel power plant as an example.

Results. The performed analysis of different methods for modeling fire dynamics shows the possibility of using different fire simulation methods in the analysis of the fire hazard of buildings and facilities. The most dangerous fire development scenarios were modeled and the obtained results were analyzed on the example of a specific typical NPP facility in the NPP emergency power supply system. The redundancy requirements for these systems were taken into account to ensure tolerance to system failures in case of process failures and external effects on these systems.

Conclusion. Since the CFD method is the most universal of the existing deterministic methods, it can be widely used to determine/revise the requirements for fire resistance of load-bearing and enclosing structures at NPP premises. It is possible to apply CFD-based fire modeling for the fire hazard of various buildings and facilities. This model is particularly effective in justifying the sufficiency of fire resistance requirements established for structures to prevent the spread of fire beyond the fire zone within the estimated burnout time of the entire fire load The obtained regularities can be used in the development/revision of regulatory documents on fire safety at operating NPPs and NPPs under construction.

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