## 2 Modeling and Parameter Adjustment
### Burner Characteristics  
In accordance with the methodology described in study [10], the fire source was defined using nine wood stacks to ensure consistency and comparability across the ventilation scenarios. The maximum value of the heat release rate (HRR) was determined using a specialized computational program, based on parameters such as calorific potential, ventilation conditions, and total combustible mass. This analysis yielded a peak HRR of  
Figure 4: Configuration of points monitoring (**a,b**) and slice planes used to record temperature, velocity, visibility, and pressure parameters (**c**).  
4350 kW, sustained for 960 s. The HRR evolution followed the theoretical t-squared (t\({}^{2}\)) fire growth model (HRR = \(\alpha\cdot\)t\({}^{2}\)), which reliably captures the development of fires during their growth phase [46]. The fire scenario incorporated an ignition delay of 10 s, a growth rate \(\alpha\) = 0.1876 kW/s\({}^{2}\), and a decay rate of 0.00293 kW/s\({}^{2}\). The total combustible surface area was 80.325 m\({}^{2}\), with a heat release rate per unit area (HRRPUA) of 100.0 kW/m\({}^{2}\). A ramp up function was applied to simulate the progressive increase in HRR, ensuring a realistic fire development profile across all simulated ventilation configurations.  
The combustion settings allowed for the detailed configuration of fire parameters. In this study, the heat of combustion per unit mass of oxygen was set at 13,100 kJ/kg, with a radiative fraction of 0.35, a carbon monoxide yield of 0.042, and a soot yield of 0.198, ensuring the accurate simulation of both thermal behavior and pollutant emissions during fire development.  
A critical aspect in fire development is the occurrence of thermal phenomena such as flashover and backdraft. Flashover represents the critical point in a compartment fire where all combustible materials ignite almost simultaneously, marking the transition to the fully developed phase. This phenomenon is preceded by a rapid increase in heat and followed by decay and cooling phases, significantly impacting the structural behavior of exposed building elements [47]. Regarding backdraft, both temperature and the location of the ventilation opening play essential roles in its onset. Higher temperatures and lower-level openings favor the rapid occurrence of backdraft, while lower temperatures and higher-level openings delay it. This highlights the importance of temperature control and the strategic selection of opening locations to ensure firefighter safety during intervention [48; 49]. Simulating backdraft remains a complex challenge in numerical fire modeling, requiring refined reignition parameters and more realistic definitions of initial conditions to reproduce experimentally observed behaviors--especially in scenarios involving gaseous fuels and sensitive mixing regimes [50]. The FDS results window provides a detailed view of fire evolution within a compartment, including 3D smoke movement simulations, an evaluation of heat release rate per unit volume (HRRPUV), and smoke density analysis. These parameters are essential for understanding fire behavior and for developing effective ventilation and firefighting strategies.  
The building model has been previously studied in related research [10] focusing on office fires and stack effect interactions in multi-story buildings. The FDS model setup adhered to official guidelines, with mesh and time step sensitivity tests ensuring numerical stability. The error between experimental and numerical results is within accepted limits (5-10% mean relative error), confirming the model's reliability for smoke and fire dynamics simulations in high-rise structures.  
The fire source was validated experimentally and numerically in an independent study providing a reliable basis for HRR and fire growth parameters [10].