Numerical validation of spatial temperature distribution in Decker’s experiment using FDS program for fully opened configuration

This paper presents a comprehensive numerical validation and performance analysis of fire-induced thermal environments in a large scale garage using Decker’s experimental data as a benchmark. Numerical simulations were performed using Fire Dynamic Simulator (FDS) to evaluate the longitudinal temperature distributions for different Heat Release Rate (HRR) from 200 kW to 4 MW for the thermostat at X = 14.3 m. The model shows a high level of accuracy with the average relative error for the peak temperatures being less than 7.1%. The study also presents the transient behavior of smoke and heat beyond validation. In the 4 MW scenario, the ceiling temperature reached 806 °C, which is a serious threat to the structural stability. Results also indicate a significant disparity between the smoke production and the exhaust capacity; the garage was totally smoke-logged within 60 s, thus effectively depleting the Available Safe Egress Time (ASET). These results highlight the importance of the combination of passive fire protection, such as thermal insulation, with optimized mechanical ventilation systems to achieve both the structural integrity and life safety during high intensity fire events.