Phase Doppler Interferometry Measurements in Water Sprays Produced by Residential Fire Sprinklers.
Phase Doppler Interferometry Measurements in Water
Sprays Produced by Residential Fire Sprinklers.
Widmann, J. F.
Fire Safety Journal, Vol. 36, No. 6, 545-567, September
water sprays; sprinklers; drop sizes; fire suppression;
size distribution; velocity measurement; interferometry
A phase Doppler interferometry (PDI) system was used to
characterize the water sprays produced by four
residential fire sprinklers. Four pendent sprinklers
with K-factors ranging from 7.2 x 10-5m3s-1kPa-0.5 (3.0
gal min-1 psig-0.5) to 1.35 x 10-4m3s-1kPa-0.5 (5.6 gal
min-1 psig-0.5) were investigated. The measurements
include (arithmetic mean diameter, volume mean diameter,
Sauter mean diameter), mean velocity (axial and radial
components), and liquid volume flux. The effect of water
pressure on drop size was also investigated. the mean
drop size (flux-averaged volume diameter, D30) was found
to be proportional to P-1/3 over the range 93 kPa