Keywords
critical velocity
backlayering length
Froude number
transformable element
How to Cite
Abstract
The essence of the problem lies in the experimental study of the laws governing the changes in the aerodynamics of air flow and the most important ventilation parameters, taking into account the effect of fire. During the experiments, the aerodynamics of the tunnel is complicated by the presence of additional resistance, and the variables will be: the slope of the tunnel, the heat release rate, the cross section of the tunnel, the ratio of the width of the tunnel to the height, the fill factor of the tunnel by transport. The solution to the problem is an improved ventilation technology in case of fires to save lives. The aim of the research is to study the critical velocity, the backlayering length and the gradient-factor using numerical and physical models, as well as mathematical analysis for the downward movement of fresh air, when the fresh air inlet is above the fire level. The scale of the physical models is 1:40 and 1:60. Numerical models are full scale using of modern engineering technique Pyrosim and Fluent. The generalization of the results is carried out using piece-wise constant functions. The obtained results are also be compared with similar results known from scientific literature.
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Copyright (c) 2021 Omar LANCHAVA, Nicolae ILIAS, Sorin Mihai RADU, Leon MAKHARADZE, Teimuraz KUNCHULIA, Nino ARUDASHVILI, Zaza KHOKERASHVILI