О вопросах верификации результатов моделирования теплового потока полевым методом

Abstract

Purpose. One of the fire safety requirements is the creation of conditions for preventing fire spread between buildings. This requirement is implemented by observing fire prevention distances (breaks) between buildings and structures. Requirements for fire prevention distances (breaks) are established in regulatory documents. In some cases, the implementation of these requirements is either technically impossible, or associated with significant economic costs, when the further operation of the facility is impractical. To solve this problem, it is possible to reduce fire prevention distances (breaks) between facilities under protection, provided that the engineering calculation confirms the impossibility of fire spread to a neighboring facility by a heat flow. The accuracy of the results obtained by the method of calculating fire distance (break) directly affects the level of fire hazard in the facility under protection, and verification in the calculation models used within the framework of this method is an important stage in its development and improvement. Methods. For research, methods of analysis and computer simulation with the help of the Fire Dynamics Simulator (FDS) software product are used. Findings. The simulation of a heat flow during heptane pan burning is performed. The results obtained during the simulation are compared with the results of a full-scale experiment. Recommendations for setting FDS parameters for heat flow simulation are formulated. Research application field. The study results can be applied in the calculation of fire prevention distances (breaks) by the field method using Fire Dynamics Simulator software product. Conclusions. The model created by means of FDS requires mandatory refinement of the parameters, since not in all cases the default values correctly describe the simulated process. The study of the issue of heat flow simulation in FDS requires further research. In the course of numerical experiments, it is found that when calculating the incident heat flux, it is necessary to pay attention to setting such parameters as discretization of the solid angle, the fraction of energy spent on radiation, CO and soot release. For correct assessment of the incident heat flux, it is recommended to simulate combustion by solid angle correction with a step in 100 until the value of the incident heat flux stabilizes within a narrow range.