MODIFIED ZONAL MODEL FOR CALCULATING OF THE FIRE GAS DYNAMICS IN THE ROOM TAKING INTO ACCOUNT THE FORM OF CONVECTIVE COLUMN
https://doi.org/ 10.18322/PVB.2015.24.12.33-39
Abstract
It is developed a modified zonal model for calculating the gas dynamics of fire in the room, taking into account the effect of walling the house in the form of convective column formed above a source of combustion. Contrast to the known zonal models is to use to calculate the mass flow rate through the cross section of the column suggested a one-dimensional differential equation. An experimental installation with dimensions 1,5x0,7x0,7 m is created to study the dynamics of fire hazards in small-scale room. Results of experiments on the study of the shape and angle of convective column are presented. In the experiments, a combustible material (phenol-formaldehyde resin filled with wood flour) was located in the center, in the corner of the room (the constraint of two surfaces), and also near the wall in the middle of it (tightness one surface). Visualization of the flow showed that at all locations of combustible material boundary of a convective column is first propagated upward with a constant angle of disclosure about half the height of the room, and then the above-mentioned angle changes only slightly. There are obtained experimental data confirm the theoretical results, using the proposed equation for calculating the mass flow through the cross-section of a convective column. It is shown that the use of approach of unlimited free-convective jets in the zonal models to describe the parameters of the convective column does not reflect the real thermodynamic picture of the fire development in the room.
About the Authors
S. V. Puzach
State Fire Academy of Emercom of Russia
Russian Federation
Russian Federation
S. A. Kolodyazhnyy
Voronezh State University of Architecture and Civil Engineering
Russian Federation
Russian Federation
N. V. Kolosova
Voronezh State University of Architecture and Civil Engineering
Russian Federation
Russian Federation
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Review
For citations:
Puzach S.V., Kolodyazhnyy S.A., Kolosova N.V. MODIFIED ZONAL MODEL FOR CALCULATING OF THE FIRE GAS DYNAMICS IN THE ROOM TAKING INTO ACCOUNT THE FORM OF CONVECTIVE COLUMN. Pozharovzryvobezopasnost/Fire and Explosion Safety. 2015;24(12):33-39. (In Russ.) https://doi.org/ 10.18322/PVB.2015.24.12.33-39
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