Experimental Study of a Water Droplet Impinging on a Liquid Surface.
Experimental Study of a Water Droplet Impinging on a
Liquid Surface.
(329 K)
Manzello, S. L.; Yang, J. C.
Experiments in Fluids, Vol. 32, No. 5, 2002.
Keywords:
droplets; water; liquid surfaces; thermophysical
properties; surface tension; impingement
Abstract:
An experimental study is presented for water droplet
impingement on a liquid surface. The impaction process
was recorded using a high-speed digital camera at 1000
frames per second. The initial droplet diameter was
fixed at 3.1 mm 0.1 mm and all experiments were
performed in atmospheric air. The impact velocity was
varied from 0.36 m/s-2.2 m/s thus varying the impact
Weber number from 5.5-206. The impacted liquid surface
consisted of two fluids, namely water and
methoxy-nonafluorobutane, C4F9OCH3 (HFE7100). The depth
of the water and HFE-7100 pool was varied from 2 mm to
25 mm. The collision dynamics of water in the HFE-7100
pool was observed to be drastically different than that
observed for the water droplet impingement on a water
pool. The critical impact Weber number for jet breakup
was found to be independent of liquid depth.
Water-HFE7100 impact resulted in no jet breakup over the
range of velocities studied. Therefore, no critical
impact Weber number can be defined for water-HFE7100
impact.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899