Flooding Criterion for Evaporative Cooling on Horizontal Semi Infinite Solids.
Flooding Criterion for Evaporative Cooling on Horizontal
Semi Infinite Solids.
(341 K)
Lederer, M. A.; diMarzo, M.; Tartarini, P.
NIST GCR 96-687; Paper 17; June 1996.
American Society of Mechanical Engineers (ASME).
National Heat Transfer Conference. ASME 31st
Proceedings. Volume 4: Interfacial Phenomena; Boiling
Heat Transfer; Thermal Hydraulics for Advanced Nuclear
Reactions. HTD-Vol. 326. August 3-6, 1996, Houston, TX,
American Society of Mechanical Engineers, New York, NY,
White, L.; Singer, R. M.; Peterson, F.; Cheung, F. B.,
Editor(s)(s), 213-217 pp, 1996.
Sponsor:
National Institute of Standards and Technology,
Gaithersburg, MD
Available from:
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Order number: PB96-202304
Keywords:
water sprays; evaporative cooling; solids; flooding;
formulations; sprays; equations; droplets
Abstract:
The evaporative cooling of a sparse spray impacting on a
hot solid is investigated to determine the limiting
condition associated with the liquid flooding of the
solid surface. The flooding condition is identified when
the evaporation rate is insufficient to remove the
amount of water being deposited on the surface. The
flooding criteria is derived as a function of the
initial single droplet volume prior to deposition, the
Evaporation-Recovery Cycle (ERC) and the area of
influence, which describes the region of the solid
surface associated with a single droplet cooling effect.
These last two quantities, the ERC and the area of
influence, are evaluated by integrating previously
obtained theoretical and experimental information with
selected experimental data obtained in this study. The
flooding criteria, while semi-empirical in its
derivation, can be generalized to all non-porous solids
under a variety of conditions. The spray is sparse and
the water droplets are considered of uniform size.
Extension to a spray with non-uniform droplet
distribution is not considered here.
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National Institute of Standards and Technology
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