Fire events in nuclear power plants represent a significant potential hazard and are an important contributor to the overall operational risks of these facilities. Consequently, a detailed understanding of fire and smoke propagation behaviour in such applications is required for fire performance-based engineering and risk assessment. This paper presents computational fluid dynamics modelling of a postulated fire scenario and occupant evacuation in a typical multi compartment nuclear building. The NIST Fire Dynamic Simulator (FDS) was used to model fire and smoke propagation by adopting large eddy simulation turbulence modelling approach. FDS simulation benchmarking was first performed against available experimental data of a two-storey compartment. Following this, a study was conducted to understand the smoke propagation, distribution of temperature, toxic gas concentrations, and smoke optical density inside a typical multi-compartment nuclear building. The effect of ventilation on the fire and smoke spread was also investigated. Human evacuation modelling was conducted to determine the required evacuation time and toxic gas dose for each occupant. The FDS predicted smoke parameters, including smoke optical density and toxic gas concentrations, were used as inputs to the evacuation modelling. The results suggest that ventilation flows decrease the smoke optical density due to smoke dilution and thereby result in a shorter time for the occupants to evacuate.

核电厂火灾事件是一种重大的潜在危害，是这些设施整体运行风险的重要因素。因此，基于火灾性能的工程和风险评估需要详细了解此类应用中的火灾和烟雾传播行为。本文介绍了典型多隔间核建筑中假设火灾场景和人员疏散的计算流体动力学模型。NIST Fire Dynamic Simulator (FDS) 用于通过采用大涡流模拟湍流建模方法对火灾和烟雾传播进行建模。FDS 模拟基准测试首先针对两层隔间的可用实验数据进行。在此之后，进行了一项研究以了解烟雾的传播，典型的多隔间核建筑内的温度分布、有毒气体浓度和烟雾光​​密度。还研究了通风对火灾和烟雾蔓延的影响。进行人员疏散模型以确定每个居住者所需的疏散时间和有毒气体剂量。FDS 预测的烟雾参数，包括烟雾光密度和有毒气体浓度，被用作疏散建模的输入。结果表明，由于烟雾稀释，通风流量降低了烟雾光密度，从而缩短了居住者疏散的时间。进行人员疏散模型以确定每个居住者所需的疏散时间和有毒气体剂量。FDS 预测的烟雾参数，包括烟雾光密度和有毒气体浓度，被用作疏散建模的输入。结果表明，由于烟雾稀释，通风流量降低了烟雾光密度，从而缩短了居住者疏散的时间。进行人员疏散模型以确定每个居住者所需的疏散时间和有毒气体剂量。FDS 预测的烟雾参数，包括烟雾光密度和有毒气体浓度，被用作疏散建模的输入。结果表明，由于烟雾稀释，通风流量降低了烟雾光密度，从而缩短了居住者疏散的时间。