- Author
-
Sheppard, D. T.
- Title
- Laser Measurements of Fire Sprinkler Sprays. BFRL Fire Research Seminar. VHS Video.
- Coporate
- Underwriters Laboratories, Inc., Northbrook, IL
- Report
-
Video,
March 20, 2001,
- Keywords
-
sprinklers
|
sprays
|
drop sizes
|
droplets
- Abstract
- In order to model the spray from a fire sprinkler, one needs to prescribe the initial distributions of the droplet size, speed and direction. A very promising technique for measuring these initial conditions is being explored at Underwriters Laboratories and Northwestern University with support from the Building and Fire Research Laboratory at NIST. As part of a three year study, both PIV and PDI measurements of the spray within 1 m of the sprinkler itself have been made. The information has been used by the Fire Dynamics Simulator to better predict the flux of water from a sprinkler. The effort this past year has focused on refining the sprinkler water flux calculations in FDS using a fundamental analysis of the physics of sprinkler sprays and using experimental results with real sprinklers. In the previous year, measurements were made in the immediate vicinity of sprinklers in order to develop information about droplet characteristics as they left the sprinkler. This year, experiments have been conducted in a 1.5 m by 1.5 m vertical plane to measure droplet trajectories. Droplet velocities have been measured 1.2 m below sprinklers out to a radial distance of 1.6 m in the presence of cold plumes and 50 kW fires. The measurements at the same elevation as the sprinkler showed how the spray lifted as a result of the fire.