Full-scale experimental study on fire suppression performance of a designed water mist system for rescue station of long railway tunnel

Abstract

Rescue stations have been newly designed in some super-long mountain railway tunnels of China such as over 30 km long, as a new type of strategic counteract design for fire accident in tunnels. Water mist fire suppression systems are needed to be installed in such rescue stations to control the train fire. However, there is no design engineering experience for it. In this article, a full-scale experimental facility was built to study the fire suppression performance of water mist system in such railway tunnel rescue station. A series of full-scale tests was preliminarily conducted considering the fire position was on top of, inside, and under the train carriage with gasoline pool fire and wood crib fire used as fire sources. A design of water mist suppression system for such a fire scenario was presented, and its performance was tested. Experimental data on temperature, CO concentration, and radiation flux were collected and analyzed. The results showed that the water mist system could control fires, cool the air temperature in the rescue station, and strongly reduce the radiant heat flux in the vicinity of the fire source under various ventilation conditions. However, the visibility of the rescue station was much deteriorated after the injection of water mist, so that emergency lights and evacuation lights are necessary for personnel evacuation. The changes of fire extinguishing time with longitudinal ventilation velocities showed that longitudinal ventilation could provide both favorable and unfavorable conditions for water mist fire extinguishment. So, to achieve efficient fire suppression performance of water mist system, attention might

Experimental investigation of atomized water droplet initial parameters influence on evaporation intensity in flaming combustion zone

“…Conclusions made on the base of received results can be used to develop the extinguishing technologies of apartment and industrial buildings and constructions [25][26][27], spacecrafts and orbital stations [28][29][30], forests and plantations [31][32][33][34]. In particular marked parameter ΔR dependences on U m , R m , T w , U g , γ and ψ can be used for determination of water atomization required parameters and also a water droplet supply timeline for full combustion source liquidation.…”

Rates of High-Temperature Evaporation of Promising Fire-Extinguishing Liquid Droplets

“…At identical values of heating temperature and heat fluxes, the rates of heating and evaporation of the latter may be higher by 15%-25% in comparison with other fire-extinguishing compositions. Since the time of localization and extinguishing of fires matter, the corresponding acceleration of heating and evaporation of droplets may be important in the development of promising technologies for suppressing forest fuel combustion [45][46][47][48][49].…”

Experimental and Numerical Analysis of the Cooling Performance of Water Spraying Systems during a Fire

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