- Author
-
Liebman, I.
|
Richmond, J. K.
- Title
- Suppression of Coal-Dust Explosions by Passive Water Barriers in a Single-Entry Mine.
- Coporate
- Bureau of Mines, Pittsburgh, PA
- Report
-
RI 7815,
February 1974,
38 p.
- Distribution
- Available from National Technical Information Service
- Keywords
-
dust explosions
|
mine fires
|
suppression
|
fire extinguishing agents
|
coal dusts
|
flame propagation
- Identifiers
- coal mine health and safety; fire and explosion prevention
- Abstract
- A study is in progress to determine the effectiveness of passive water barriers in suppressing coal dust explosions. a 2.9 ft (3) capacity water filled plastic tub was found effective in suppressing dust explosions propagating at speeds of 250 to over 1000 ft/sec. Work directed at determining the limitations of water barriers showed that the passive water barrier technique is also feasible for the suppression of weak dust explosions-propagating at speeds of 100 to 250 ft/sec. For relatively slow accelerating flames, dynamic wind forces appears to be the important quantity govering fragmentation of the plastic tub and subsequent water release dispersion, whereas dynamic impulse appears to be the significant quantity for rapidly accelerating flames. The acoustic approximation (relation between static pressure and flame or wind speed) is shown to be valid in a long single mine entry. This relationship appears to be useful in predicting the regions within a long single entry where passive water barriers are effective in quenching a dust explosion.