- Author
- Ingason, H.
- Title
- Model Scale Tunnel Fire Tests: Sprinkler.
- Coporate
- SP Swedish National Testing and Research Institute, Boras, Sweden
- Report
- SP REPORT 2006:56, 2006, 58 p.
- Keywords
- tunnels | fire tests | scale models | sprinklers | nozzles | ventilation | water sprays | heat release rate | fire spread | experiments | scaling | water flow | application rate | fire load | gas temperature | deluge systems | gas concentration
- Identifiers
- debate on use of water spray systems in tunnels; Japanese experience; scaling theory; critical water application rate; plot of data using deluge A system; deluge system B; longitudinal ventilation; sprinkler nozzle
- Abstract
- A literature survey of the use of water spray systems in tunnels is presented together with arguments and a discussion of the use of such systems. Further, a summary of available research related to testing is given. It shows that there is a lack of systematic studies dealing with important parameters such as longitudinal flow, Heat Release Rate (HRR), fire spread and thermal and toxic environment. A model scale study (1:23) was carried out in order to improve the basic understanding of water spray systems in longitudinal tunnel flow. The water spray system consisted of commercially available axial-flow hollow cone nozzles. Tests with both a deluge system made of 12 nozzles placed directly above the fire source and a water curtain system consisting of 4 nozzles placed either downstream or upstream of the fire source were carried out. A wood crib was used to simulate the fire source, which was designed to correspond to a HGV (Heavy Goods Vehicle) fire load in large scale. A second wood crib was used as a target pile and was placed downstream the ignited wood crib. The parameters varied were the water flow rate and water pressure, the longitudinal ventilation rate and the arrangement of the nozzle system. Possible fire spread between wood cribs, with a free distance corresponding to 15 m in large scale, was investigated.