Citation

Segovia JFP, Beji T, Merci B. Fire Technol. 2017; 53(4): 1669-1703.

Copyright

(Copyright © 2017, Holtzbrinck Springer Nature Publishing Group)

DOI

10.1007/s10694-017-0654-2

PMID

unavailable

Abstract

The aim of this paper is to analyse the application of the Peatross-Beyler (P&B) correlation (Fire and safety science--Proceedings of the fifth international symposium, 1997) to calculate the Mass loss rate (MLR) for a pool fire in a confined and ventilated enclosure for a range of conditions. The experimental references considered are the PRISME-SI-D1, D2 and D6 tests (Prétrel et al. in 9th International seminar on fire safety in nuclear power plants and installations, 2005), conducted by the Institut de Radioprotection et de Sûreté Nucléaire. The dimensions of the enclosure used in the experiment are 5 m in length, 6 m in width and 4 m in height. A pool fire, 0.4m20.4m20.4,hbox {m}^2 hydrogenated tetrapropylene (TPH, C12H26C12H26hbox {C}_{12}hbox {H}_{26}), is located in the center of the room. The compartment is connected to the outside through an inlet and outlet. The P&B correlation is implemented as a boundary condition in computational fluid dynamics calculations. The MLR outcome depends on the average O2O2hbox {O}_2 concentration in a predefined volume and the characteristics of the fuel. The influence of the size and location of the predefined volume, the ventilation branch position (at 1 m and 3.65 m from the floor) and the Renewal Rate (RrRrR_r) (4.7h−14.7h−14.7,hbox {h}^{-1} and 8.4h−18.4h−18.4,hbox {h}^{-1}) are studied. Two types of O2O2hbox {O}_2 predefined volumes have been tested: layer and ring. The layer volume is located in the low part of the compartment, the base of the volume spanning the compartment floor. The ring is a volume around the pit. It is assumed for both approaches that the measured O2O2hbox {O}_2 is representative of the available oxygen for the flame. The P&B boundary condition predicts the influence of the vitiation on the MLR. Other methods, such as imposing the MLR expected in open condition, overpredict the amount of injected fuel. The results show that the P&B correlation provides good agreement with the experimental data. The deviation between experimental data and numerical prediction for the average MLR in the best case is −5.0% with absolute values of 0.004 kg/s and 0.0038 kg/s for the experiment and the simulation respectively for case PRS-SI-D1. The MLR calculation is influenced by the position of the ventilation opening and the RrRrR_r. The temperature and O2O2hbox {O}_2 concentration profiles are significantly influenced by the ventilation configuration. These differences are related to the transport of the injected air from the inlet to the floor by density difference.

Language: en