Effect of Dissolved Gasses on Spray Evaporative Cooling With Water.
Effect of Dissolved Gasses on Spray Evaporative Cooling
With Water.
(722 K)
Tinker, S. C.; diMarzo, M.
NIST GCR 96-687; Paper 16; June 1996.
Sponsor:
National Institute of Standards and Technology,
Gaithersburg, MD
Available from:
National Technical Information Service
Order number: PB96-202304
Keywords:
water sprays; evaporative cooling; water; solid
surfaces; droplets; hot surfaces; drop sizes; size
distributions; experiments; data processing
Abstract:
An experimental investigation of the effect of
non-degassed water used to cool a solid surface is
presented. The solid surface is subjected to thermal
radiant input from three panels positioned above it.
The water is deposited on the surface in the form of a
sparse spray with droplets of about 10 ml. Previous
experiments with degassed water are compared with these
new experiments and the effect of dissolved gasses is
quantified in terms of the overall transient thermal
behavior of the solid. A lower steady-state average
temperature is achieved when gasses are not removed from
the water. This result suggests that the configuration
of the liquid droplets on the surface is different and
that the radiant heat input into the droplet is altered
by the gas bubbles present in the deposited droplet.
This information provides guidance in practical
applications such as sprinkler suppression systems where
water damages are a concern.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899