9/11 Fire Behavior and Combustion

9/11 Fire Behavior and Combustion

Introduction

On the morning of September 11, 2001, a hijacked commercial airplane attacks each of the twin towers of the World Trade Center in New York City. The twin towers were damaged by a combination of the fire ignited by the fuel and plane impact. In the history, it is the first time when plane impact has been destroyed in such a destructive manner. To model the fire and smoke behavior, the structural collapse was investigated as both the towers were damaged completely. The primary source for estimating the exterior damage was photographs and videos which showed the exterior damage to both of the buildings and the fire progression. a portion of the jet fuel was also generated by the collision of both of the towers that spread widely within the tower.

Discussion

On the basis of assumptions and analysis, the behavior of fire in the twin towers of World Trade Center (WTC) on September 11, 2001 is estimated. Significant structural damage was produced with the collision of hijacked place with both of the towers which generated a magnificent fire. The fireball consumed the fuel and it was then lost as an ignition source resulted in the production of a pressure pulse that altered the ventilation for the fires and broke the windows. plume was generated by the subsequent fire. By using the Fire Dynamics Simulator (FDS), the fire and smoke behavior were stimulated.

The most important single parameter for each tower fire is the total heat release rate (HRR) which is determined. For the north tower two bounding scenarios were assumed for the fuel distributions and interior damage. For each scenario, to determine which scenario seemed more appropriate, smoke behavior and the simulated visible fire outside the tower were compared with the video and photographic records. Within each tower, estimates of the likely thermal environment are provided by the simulations for the two scenarios (Baum and McGrattan, 2004).

Before the attack, there were several buildings in the World Trade Center (WTC) and all were of different sizes located in lower Manhattan as shown in the map below. The north and south towers that was considered as a significant tourist attraction and a symbol of the city. On the map, North, is commonly understood by New Yorkers, and is determined in lower Manhattan by the rectangular street grid. in these street-grid coordinates, the twin towers were aligned with the rectangular thickness of 1.04 m. 26 (Baum and McGrattan, 2004).

Figure 1: The layout of the World Trade Center

Tower and estimation was made by the government sources about the plane. United Airlines, Flight 175, a Boeing 767-222 was the second hijacked plane travelling at about 265 m/s (590 miles per hour) and carrying about 31,000 L (8200 gallons) of fuel. The 767-200 series planes had a wing span of 47.6 m (156 ft), an overall length of 48.5 m (159 ft 2 in).

In both the towers, the thermal environment produced by the fires is estimated by ...