A numerical model is presented for spectral characteristics of radiation coming from a pool fire flame. The case studies are 1.75 m × 1.75 m and 2.5 m × 2.5 m Kerosene pool fires. Transient heat and mass transfer of the system was solved using a CFD model of a 4 m × 4 m × 5 m rectangular domain built in Fire Dynamic Simulator (FDS) with LES of turbulence and a two-step combustion reaction. Transient profiles of gas compositions, soot concentration and temperature along a line of sight of an imaginary sensor were collected from the CFD simulations, and instantaneous solutions of the thermal radiation along the line were calculated using high-resolution LBL spectral absorption profiles of combustion gases together with a model for soot absorption coefficient, based on spectrally dependant complex index of refraction. The transient spectra, consisting of numerous instantaneous intensity solutions, were then averaged and compared against the similar experimentally measured data. The line of sight and other settings of the model were carefully checked to be consistent with the experiments performed for the same system. The modelling results revealed the strong absorption effect of cold atmospheric gases while the emission peak of hot CO₂ at ~2200 cm⁻¹ in fire is still quite distinguishable from the spectral profile of hot blackbody even at 23 m away from the centre of the flame. This emission peak can be therefore used for detection of the fire. The spectral changes of the spectrum are explained and a sensitivity analysis is performed to study the effects of the sensor's distance from the pool, pool size, and modelling and operational conditions, such as relative humidity and radiative fraction.

针对池火火焰辐射的光谱特性，提出了一个数值模型。案例研究为1.75  m  ×1.75 m和2.5  m  ×2.5 m煤油池火灾。使用4 m  ×4  m的CFD模型解决了系统的瞬态传热和传质问题  ×5 m矩形区域，内置于具有LES湍流和两步燃烧反应的Fire Dynamic Simulator（FDS）中。从CFD模拟中收集了沿虚构传感器视线的气体成分，烟灰浓度和温度的瞬态曲线，并使用高分辨率的燃烧气体LBL光谱吸收曲线共同计算了沿该线的热辐射的瞬时解。基于光谱相关的复杂折射率的烟灰吸收系数模型。然后，将由众多瞬时强度溶液组成的瞬态光谱求平均值，并与类似的实验测量数据进行比较。仔细检查了模型的视线和其他设置，以与针对同一系统执行的实验一致。建模结果表明，冷空气对大气有很强的吸收作用，而热CO的排放峰即使在距火焰中心23 m处，在约2200 cm ^-1处的₂仍与热黑体的光谱轮廓仍有很大区别。因此，该发射峰可用于火灾的检测。解释了光谱的光谱变化，并进行了灵敏度分析，以研究传感器距水池的距离，水池大小以及建模和操作条件（例如相对湿度和辐射分数）的影响。