The use of CFD-FDS modeling for establishing performance criteria for water mist systems in very large fires in tunnels

In this study a computational fluid dynamic (CFD) model was applied to a series of full-scale fire tests of water mist systems conducted in 2006 in the San Pedro de Anes test facilityl in Spain. Data were collected on the heat release rates (HRR) of very large test fires involving wood pallets and plastic pallets under controlled conditions. Thermocouples placed on the tunnel ceiling and at different distances from the fire recorded temperatures throughout the fire tests. The tests provided valuable insight into the dynamics of water mist interacting with very large fires in a tunnel. The fires were more dynamically complex than assumed in selecting indicators of performance. To assist in understanding the dynamics of such fires and to aid in identifying reproducible global performance criteria as an alternative to single-point measurements, the Marioff San Pedro tunnel fires were modeled using a CFD model. The purpose was to evaluate the performance of water mist systems over a broader range of performance indicators than could be measured during full-scale tests. The NIST Fire Dynamics Simulator version 4 (FDS4), a CFD model with a water mist spray nozzle algorithm, widely used in fire science and engineering, was used to simulate the Marioff San Pedro tunnel fires. There is presently extensive international activity by many agencies in applying CFD to tunnel safety problems. However, there are numerous challenges involved in applying a CFD model, with discipline and intent for accuracy, to very large fires interacting with water mist. This paper discusses how specific modeling challenges were approached for this study. The paper illustrates that CFD modeling is a powerful tool for understanding the global benefits of water mist systems (A). For the covering abstract of the conference se ITRD E216860.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/9789185829255
• Authors:
  • MAWHINNEY, J R
  • TRELLES, J
• Publication Date: 2008

Language

• English

Media Info

• Pagination: pp29-42
• Monograph Title: Proceedings from the Third International Symposium on Tunnel Safety and Security, Stockholm, Sweden, March 12-14 2008
• Serial:
  • SP RAPPORT
  • Issue Number: 2008:11
  • Publisher: SP Sveriges provnings- och forskningsinstitut, Sweden
  • ISSN: 0284-5172

Subject/Index Terms

• TRT Terms: Conferences; Fire extinguishers; Fires; Mist; Safety; Simulation; Tests; Trucks; Tunnels
• Uncontrolled Terms: Full scale
• Subject Areas: Motor Carriers; Safety and Human Factors; I25: Design of Tunnels; I85: Safety Devices used in Transport Infrastructure;

Filing Info

• Accession Number: 01141060
• Record Type: Publication
• Source Agency: Swedish National Road and Transport Research Institute (VTI)
• ISBN: 978-91-85829-25-5
• Files: ITRD
• Created Date: Sep 30 2009 8:59AM