On the Collision Dynamics of a Water Droplet Containing an Additive on a Heated Solid Surface.
On the Collision Dynamics of a Water Droplet Containing
an Additive on a Heated Solid Surface.
(2002 K)
Manzello, S. L.; Yang, J. C.
Mathematical, Physical and Engineering Sciences Royal
Society of London, Series A. Vol. 458, No. 2021.
Proceedings. 2002, London, England, 2417-2444 pp, 2002.
Keywords:
water droplets; additives; heated surface; droplets
Abstract:
An experimental study is presented for water droplet
impingement containing an additive upon a heated
stainless steel surface. A solution of 30% (mass
fraction) sodium acetate trihydrate, CH3COONa3H2O was
used for the experiments. The impaction process was
recorded using a high-speed digital camera at 1000
frames per second. The initial droplet diameter was
fixed at 2.7 mm 0.1 mm, and all experiments were
performed in atmospheric air. Three different impact
Weber numbers were considered, namely 15, 80 and 181.
The droplet evaporation lifetime was measured as a
function of temperature to determine the Leidenfrost
temperature of 30% (mass fraction) sodium acetate
trihydrate. Collision dynamics were investigated for
each impact Weber number with the temperature of the
stainless steel surface varied from 20 C to above the
Leidenfrost temperature of 30% (mass fraction) sodium
acetate trihydrate. The temporal variation of the liquid
film diameter was measured as a function of temperature
for each impact Weber number. Experiments were also
performed using water for direct comparison of the
collision dynamics to the additive containing droplets.
The collision dynamics were observed to be different for
water droplets containing an additive at low impact
Weber number but became increasingly similar as the
impact Weber was increased.
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National Institute of Standards and Technology
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