2021-2_Pages_19-26

УДК 614.841.42                                            DOI: 10.37657/vniipo.pb.2021.76.10.002

N.P. Kopylov,  E.Yu. Sushkina, A.E. Kuznetsov, V.I. Novikova

Experimental assessment of the influence of radiant heat transfer on the transition of a crown fire to settlements

Abstract

Crown fires are the main threat of the combustion transfer from the forest to objects located in it. Fire services dealing with forest fires face the problem how to protect these objects from forest fires. It is proposed to treat the object with retardant solutions before a forest fire approaches.

To assess the effectiveness of such tactics for fire protection of objects when exposed to a heat flow from the combustion front there were carried out experiments on large-scale crown fire models. A crown fire is simulated with a pile of wood with a heat release rate of ≈ 13 MW  m^–2. The wind is generated by fans, its speed is close to the speed at which a forest fire occurs.

Measurements of the heat flux density, medium temperature, and the density of sparks falling downwind of the fire front at different distances and heights were carried out.

Calculations were carried out to assess the impact of heat flow on buildings of IV–V degrees of fire resistance. The results obtained are compared with experimental data and they are in good agreement. There have been determined the distances from the fire front at which the fire protection with  retardant solutions  is effective for structures of IV–V fire resistance degrees at radiant heat exchange.

Keywords: forest fire, forest riding fire, heat exchange in a forest fire, simulation of a riding fire, fire protection of objects, retardants for protection against forest fires

Referens

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Received March 22, 2020

Аuthors:

Nikolay P. Kopylov – Doctor of Technical Sciences, Professor, Main Researcher;

Elena Yu. Sushkina – Candidate of Technical Sciences, Head of Department – Academic Secretary. Е-mail: np.nanpb@mail.ru;

Aleksandr E. Kuznetsov – Candidate of Technical Sciences, Head of Department;

Viktoriya I. Novikova – Researcher.

All-Russian Research Institute for Fire Protection (VNIIPO), the Ministry of the Russian Federation for Civil Defence, Emergencies and Elimination of Consequences of Natural Disasters (EMERCOM of Russia), Balashikha, Moscow region, Russia.