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Unsteady flow of gases in a mine ventilation network - a numerical simulation |
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Unsteady flow of gases in a mine ventilation network - a numerical simulation Authors: W. Dziurzyński, J. Krawczyk
In this article the authors present two methods of describing the flow of air and fire gases in ventilation networks. Both methods make use of the approximation of one-dimensional flow. The more detailed model treats air as a compressible medium and is based on the complete set of mass, momentum and energy conservation equations. The second model discounts the influence of temporary derivatives of pressure, density and velocity on the course of the phenomena researched, which results in a simpler description. The authors have applied identical fire and fire gas transport models, as well as a similar model of heat exchange with the rock mass. These methods have led to the development of computer programmes. Subsequently, we compared the results of calculations of non-stationary states caused by fires in headings ventilated by an upward current and a downward current for a single mesh networks. The data obtained are of a similar nature, although they do differ in terms of quantity. In one of the examples a more detailed model provided for the reversal of flow, while according to the quasi-static description the direction was maintained. Finally, the authors offer an interpretation of the findings and the prospective applications of the detailed description.
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2011