Annotation:
The need to organize emissions of a large amount of gas arises in a number of technological operations related to the transportation, storage and processing of combustible gases, preparation and purging of containers, etc. The largest emissions occur during emergencies. For a correct assessment of the level of fire hazard and the choice of efficient ways to prevent fires, it is required to study in detail many defining parameters. First of all these are the limiting conditions for stabilization and extinguishing of diffusion flame of the torch.
An analysis was made of the formation and stabilization conditions of a diffusion torch formed during the outflow of combustible gas from various gas discharge devices. On the basis of theoretical studies based on a single physical model, analytical expressions are derived. They describe the limiting conditions for the stabilization of turbulent diffusion torches in a wide range of changes in gas outflow conditions and parameters of the surrounding atmosphere. The proposed dependences allow to evaluate the complex effect of various factors (gas composition, gas discharge velocity and direction, size and shape of vents, wind speed, oxygen concentration in the surrounding space) on the parameters of turbulent diffusion torches.
Within the framework of the study, the experimental regularities of stabilization and gas-dynamic extinguishing of turbulent diffusion torches are determined. These regularities make it possible to evaluate the influence of various factors (the degree of dilution of the combustible gas with an inert gas, the size and shape of the discharge hole, wind speed and oxygen concentration in the surrounding space) on the limiting conditions for stabilization of diffusion torches.
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