ORIGIN AND PROPERTIES OF FIRE WHIRLS.
Abstract
To determine the origin of fire whirls in fires, the origin of the vertical vorticity required to sustain them was investigated. It was found that the vertical vorticity developed by the bending upward of the horizontal vortex lines of the ambient wind boundary layer is greater than that produced by other mechanisms. The intensity and distribution pattern of the vorticity is also in agreement with the circulatory flow found to exist in experimental fire wind data. A method for estimating the intensity of fire whirls in urban fires is given which is based on the way the vorticity production scales with fire size and on existing analyses of the properties of convective vortices. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 15, 1969
- Accession Number
- AD0701927
Entities
People
- Hugo J. Nielson
Organizations
- IIT Research Institute