LES of blockage of thermal radiation to the pool surface in large double pool fires.

Abstract

Thermal radiation blockage to the pool surface plays a major role in assessing the fire growth and heat feedback to the pool surface and thereby intensity of pollution to the environment. In this work, large eddy fire simulations are performed to quantify the thermal radiation blockage to the pool surface of 0.6 m n-heptane double pool fires (DPF). The interspace between the two pools is varied from 0 to 0.6 m. The results of the air entrainment show that the considered double pool configuration is radiation dominated irrespective of the separation distances between the pools. The predicted heat feedbacks are in good agreement with the experimental results. A radiation influencing zone (RIZ) is introduced based on the percentage of the radiation contribution from the flame. RIZ is directly proportional to the flame height. Based on the opacity through the RIZ, the thermal radiation blockage is calculated. The blockage of radiation from standalone fire to double fire increased to 20%. The calculated radiative heat flux to the pool surface is in good agreement with the reported measurements. In addition, the maximum deviation between calculated and measured heat fluxes of the studied DPF is 6.8%. Further, the accuracy of the present methodology is shown better than the reported literature estimations.