Louis Hardy, Anthony Collin, Mathieu Suzanne, Giacomo Erez, Rabah Mehaddi, Pascal Boulet
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引用次数: 0
Abstract
This study compares the effects on a smoke layer of water sprays injected downward, upward or according to an inclined counter-flow configuration. The impact is analyzed considering stratification, mixing and cooling effects upstream (fire side) and downstream (opening side) the position of the spray. The experiments were conducted in a 1/5th scale model reproducing a room connected to a corridor. The injection of the poly-dispersed spray was carried out in the corridor where a layer of smoke was flowing in the upper part. Thanks to the experimental configuration, there is no direct impact of the spray on the fire source and the production of smoke, but only on the hot flow of smoke. The effect of the spray was evaluated for the different directions of injection and two water feeding pressures. The measurements have shown that effective cooling of the upper layer is observed downstream of the spray. The efficiency of the cooling is dependent on the injection angle. A more or less significant heating of the lower layer is measured upstream for all the injection angles. The injection angle has an influence on the smoke mixing and cooling, an upward spray injection—either vertical or inclined—being more impactful. The strongest interaction is observed for an inclined counter-flow injection, similar to the configuration of firefighters cooling a smoke layer while moving forward in a corridor toward a fire source. Moreover, two water injection pressures were investigated: 4 and 8 bars. Increasing this pressure reduces the droplet diameter and increases the water flow rate. In the present experimental configuration, modifying the water injection pressure showed an effect, yet limited because the droplet size distribution was not strongly impacted. All experimental data are available in an open-access database for further uses.
期刊介绍:
Fire Technology publishes original contributions, both theoretical and empirical, that contribute to the solution of problems in fire safety science and engineering. It is the leading journal in the field, publishing applied research dealing with the full range of actual and potential fire hazards facing humans and the environment. It covers the entire domain of fire safety science and engineering problems relevant in industrial, operational, cultural, and environmental applications, including modeling, testing, detection, suppression, human behavior, wildfires, structures, and risk analysis.
The aim of Fire Technology is to push forward the frontiers of knowledge and technology by encouraging interdisciplinary communication of significant technical developments in fire protection and subjects of scientific interest to the fire protection community at large.
It is published in conjunction with the National Fire Protection Association (NFPA) and the Society of Fire Protection Engineers (SFPE). The mission of NFPA is to help save lives and reduce loss with information, knowledge, and passion. The mission of SFPE is advancing the science and practice of fire protection engineering internationally.